271
In conclusion, large doses of vitamin A delivered every 6 months may not be sufficient to ameliorate deficiency in some settings, perhaps as a result of other dietary deficits. Conversely, the differences in outcomes between trials may be related to severity of deprivation and burden of disease: mortality rates were higher at the sites where vitamin A was effective. Further investigation of factors that modify the efficacy of vitamin A supplementation on mortality is needed to guide policy formulation. In accordance with findings in other developing countries, Sudanese children living in poor and unsanitary environments, younger children, and those sick, stunted, wasted, or consuming diets low in vitamin A were at a significantly higher risk of dying. There were differences in mortality associated with dietary intake of vitamin A even after controlling for indicators of socioeconomic status and sanitary conditions of the home. A reduction in poverty, improvements in sanitation, and access to adequate diets should remain the goals of child survival efforts. Assuring adequate levels of intake of vitamin A by increasing dietary intake through fortification of staple foods or by providing small supplementary doses frequently may be more effective in some settings than distribution of massive doses of vitamin A. Improvement of vitamin A intake by whatever possible and effective means, including periodic distribution of large doses, continues to be of high priority in areas where the deficiency is prevalent and nutritional blindness a common and tragic occurrence.
Center for Health Statistics, November 1977. (DHEW
13.
14.
publication [PHS] 78-1650). Singer JD, Willett JB. Modeling the days of our lives: using survival analysis when designing and analyzing longitudinal studies of duration and the timing of events. Psychol Bull 1991; 110: 268-90. Muhilal, Permeisih D, Idjradinata YR, Muherdiyantiningsih, Karyadi D. Vitamin A-fortified monosodium glutamate and health, growth, and survival of children: a controlled field trial. Am J Clin Nutr 1988;
48: 1271-76. 15. Swaminathan MC, Susheela TP, Thimmayamma BVS. Field prophylactic trial with a single annual oral massive dose of vitamin A. Am J Clin Nutr 1970; 23: 119-22. 16. Gopalan C. Combating vitamin A deficiency-need for a revised strategy. In: Recent trends in nutrition. Proceedings of First International Symposium of the Nutrition Foundation of India. Oxford: Oxford University Press, 1991 (prefatory chapter). 17. Rahmathullah L, Underwood BA, Thulasiraj RD, Milton RC. Diarrhea, respiratory infections, and growth are not affected by a weekly low-dose vitamin A supplement: a masked, controlled field trial in children in southern India. Am J Clin Nutr 1991; 54: 568-77. 18. Glover J. Factors affecting vitamin A transport in animals and man. Proc Nutr Soc 1983; 42: 19-30. 19. Udomkesmalee E, Dhanamitta S, Sirisinha S, et al. Effect of vitamin A and zinc supplementation on the nutriture of children in Northeast Thailand. Am J Clin Nutr 1992; 56: 50-57.
SHORT REPORTS Simian immunodeficiency virus needlestick accident in a laboratory worker
We thank Dr Walter Willett and Dr John Orav for valuable advice throughout the study, Dr El Fatih El Samani for help in the planning and early phases of the project, the USAID mission in Khartoum for their invaluable support, the field staff whose hard work made the study possible, Dr Elizabeth Allred for her assistance in data management, Hoffinan-La Roche Task Force Sight and Life Program for provision of vitamin capsules and for conducting the assays, and Ms Jill Arnold for her assistance in the preparation of the manuscript.
This study was carried out under cooperative agreement No. DAN-0045G-SS-6067 of the Office of Nutrition, US Agency for International Development (USAID), Washington, DC, and the Harvard Institute for International Development, Cambridge, MA, USA, and the Division of Nutrition, Ministry of Health, Khartoum, Sudan.
REFERENCES 1. Sivakumar B, Reddy V. Absorption of labelled vitamin A in children during infection. Br J Nutr 1972; 27: 299-304. 2. Barclay AJG, Foster A, Sommer A. Vitamin A supplements and mortality related to measles: a randomized clinical trial. BMJ 1987;
294: 294-96. Klein M. A randomized, controlled trial of vitamin A in children with severe measles. N Engl J Med 1990; 323: 160-64. 4. Sommer A, Hussaini G, Tarwotjo I, Susanto D. Increased mortality in children with mild vitamin A deficiency. Lancet 1983; ii: 585-88. 5. Sommer A. Mortality associated with mild, untreated xerophthalmia. Trans Am Ophth Soc 1983; 81: 825-53. 6. Sommer A, Djunaedi E, Loeden AA, et al. Impact of vitamin A supplementation on childhood mortality. Lancet 1986; i: 1169-73. 7. Vijayaraghavan K, Radhaiah G, Prakasam BS, Sarma KVR, Reddy V. Effect of massive dose vitamin A on morbidity and mortality in Indian children. Lancet 1990; 336: 1342-45. 8. West KP Jr, Pokhrel RP, Katz J, et al. Efficacy of vitamin A in reducing preschool child mortality in Nepal. Lancet 1991; 338: 67-71. 9. Rahmathullah L, Underwood BA, Thulasiraj RD, et al. Reduced mortality among children in southern India receiving a small weekly dose of vitamin A. N Engl J Med 1990; 323: 929-35. 10. United States Department of Health, Education and Welfare, Public Health Service, and the Food Composition and Planning Branch of the Food and Agricultural Organization. Food composition tables for use in Africa. Rome: FAO, 1968. 11. United States Department of Agriculture, Agricultural Research Service. Composition of foods, Agriculture Handbook No. 8-1. Washington, 3.
Hussey GD,
DC, USDA, November, 1976. 12. Hamill PVV, Drizd TA, Johnson CL, et al. NCHS growth curves for children birth-18 years United States. Hyattsville, MD: National
The macaque monkey infected with simian immunodeficiency virus (SIV) is an animal model of the acquired immunodeficiency syndrome. We investigated a laboratory worker who was exposed by needlestick accident to blood from an SIVinfected macaque. Seroreactivity to SIV developed within 3 months of exposure, with antibody titres peaking from the third to the fifth month and declining thereafter. Polymerase chain reaction for SIV sequences and cultures of peripheral-blood mononuclear cells failed to show infection. Inoculation of an SIV-negative monkey with blood from the worker did not cause infection. Animal-care and laboratory workers should adhere strictly to recommended procedures to avoid accidental exposures when working with SIV-infected animals or
specimens.
virus (SIV) infection of valuable animal model for the study of the acquired immunodeficiency syndrome (AIDS).12 There is a potential risk that human beings working in research laboratories may be exposed to SIV.3 To date, however, no SIV infection in human beings has been reported. We Simian
immunodeficiency
macaques is
a
272
SEROLOGICAL ASSAYS OF SERIAL BLOOD SAMPLES FROM LABORATORY WORKER
1 =who)e-v!rus EIA (Genetic Systems), 2=peptide EIA (Genetic Systems), 3=peptide EIA (Pharmacia) ; 4=western blot with HIV-21888 strain as a source of antigen, 5=wholevirus EIA with SIV sm/Delta/B670 antigen; 6=recombinant protein-based EIA with Baculovirus-expressed SIV mac rGP140; 7 = recombinant protein-based EIA with Baculovirus-expressed SIVmac rGP110; 8=peptide EIA with a 31-aminoacid peptide from the transmembrane prctein of S]Vmac26l (amlnoacids 600-630), 9=western blot with SIVsm/Delta B670 antigen; and 10= RIPA with SIVmac251 lysate. *1 week before the accident.
report exposure of a laboratory worker to SIV by needlestick injury and describe the subsequent follow-up. In March, 1990, a technician in a research laboratory was pricked with a blood-contaminated needle while attempting to disconnect the vacutainer sleeve from the needle after taking blood from an anaesthetised SIVsm/Delta/B670-infected macaque. The animal had been inoculated with SIV 6 months earlier, had seroconverted, was SIV culture positive, and was substantially wasted. The needle, visibly contaminated with blood, penetrated a latex glove and produced a deep puncture wound and bleeding of the worker’s thumb. She immediately scrubbed the wound with povidoneiodine followed by 10% bleach. Inflammation and swelling developed at the wound site and persisted for several weeks. The technician reported no risk behaviour for human immunodeficiency virus (HIV) infection. She did not have any illness suggestive of acute retroviral infection and remained well with no clinical or laboratory evidence of immunodeficiency.
Serum samples collected 1 week before the accident, 1 week after the accident, monthly over the following 12 months, and 19 months after the accident showed no reactivity to HIV-1 by peptide enzyme immunoassay (EIA) (Genetic Systems, Seattle, USA) or by western blot (Ortho Diagnostics, Raritan, New Jersey, USA), and no reactivity to HIV-2 or SIV by whole-virus EIAs (table). By contrast, serum samples collected from June, 1990, to March, 1991, were reactive to several synthetic peptides derived from the transmembrane region of SIV and HIV-2 (table). Peptide EIA showed that antibody titre to a 31-aminoacid peptide from the transmembrane protein of SIVe25l peaked between June and August, 1990. HIV-2 western blots with HIV -21888 as a source of antigen4 (figure, panel A) showed antibodies to envelope peptide gp41 starting in July, 1990, and a weak reactivity to p26 (also called p27) in all the samples including the pre-accident sample (table). However, SIV western blots (figure, panel B) were negative for antibody in serum samples taken from March to June, 1990, and only weakly positive for p27 (gag) after July, 1990 (table). Radioimmunoprecipitation assay (RIPA) with 35Slabelled SIVmac/251-infected cells showed reactivity to the envelope protein gpl30 in serum samples from August onwards with peak intensity in the August sample (table). 1 month after the accident and monthly thereafter for 1 year, 2 x 107 peripheral-blood mononuclear cells (PBMCs) from the worker--separated by Ficoll-Hypaque gradient centrifugation-were cultured with phytohaemagglutinin.
cultures and co-cultures with normal human PBMCs were maintained for 4 weeks and examined every 3 days; no cytopathic effect was seen. Culture supernatants were negative for SIV antigen by an SIV p27 antigencapture assay (Coulter, Hialeah, Florida, USA). Cultured cells (22 day) from February, 1991, were also negative for SIV by the polymerase chain reaction (PCR). PCR amplification was done in 2 different laboratories with primers and probes from the gag5 and pol!’ region of SIV with nested amplification in pol, and with pol, L TR, and env nested primers representing consensus sequences of HIV-2 and SIV.6 SIV mac-infected and/or SIV sm/Delta/B670infected cells, including PBMCs from infected monkeys,
Primary
Western blot of exposed worker’s sera with HIV-2 antigen (strain CDC1888, panel A) and SIV antigen (panel B). Lane 1 = pre-accident serum; lanes 2 to 13 =monthly serum samples from March, 1990, to February, 1991, lane 14= negative control; lane 15= HIV-2-positive control
273
used
positive controls. Amplified products were Southern blot hybridisation with 32P-endprobed by labelled internal oligomers. PBMCs from April to September, 1990, and from December, 1990 to March, 1991, were all negative for PCR evidence of SIV. 13 months after the accident, 10 ml of blood from the worker was inoculated into a healthy, SIV-negative young Rhesus imulata macaque. The monkey was bled every 2 weeks or monthly for 10 months after inoculation; serum samples were negative for antibodies to SIV by whole-virus EIA and by synthetic peptide EIAs, and the animal showed no evidence of SIV infection by PCR. This is, to our knowledge, the first report of a person who, after percutaneous exposure to SIV-infected macaque blood, showed evidence of seroconversion with antibodies to both gag and envelope proteins within months of exposure. Efforts to isolate virus from peripheral blood and to find SIV provirus by PCR were unsuccessful. In addition, we failed to transmit SIV by inoculating a macaque with the worker’s blood. These negative results, coupled with declining antibody titres to the SIVtransmembrane-derived peptide after a peak at 3-5 months postexposure, suggest that the subject has not become persistently infected with SIV. It is unclear whether the observed serological response is an immune response to viral proteins from inoculation of the SIV-infected macaque’s blood (a vaccination-like effect)7 or an allotypic or xenotypic response to cellular antigenic determinants in the monkey cells with crossreactivity to SIV antigens.8 The time between exposure and first detection of any response does not accord with a passive transfer of antibody. Since human PBMCs can be infected with SIV,9 the observed seroreactivity without demonstrable infection in this worker is sobering. Whole-virus EIAs were less sensitive than peptide-based EIAs, SIV western blots, and RIPA in detecting seroreactivity. Systematic and intensive investigation of individuals exposed to SIV should reveal the incidence of seroconversion. Moreover, surveillance with the sensitive assays we used is needed to effectively evaluate the risk of SIV transmission to exposed workers. This report is a reminder for those working with SIV-infected animals to be cautious and to adhere strictly to recommended procedures to minimise accidental exposures.3 were
as
We thank Dr Harold Jaffe for critical review of the manuscript John O’Connor for editorial assistance.
and Mr
REFERENCES 1.
Murphey-Corb M, Martin LN, Rangan SR, et al. Isolation of an HTLV-III related retrovirus from macaques with simian AIDS and its possible origin in asymptomatic mangabeys. Nature 1986; 321: 435-37. 2. McLure HM, Anderson DC, Fultz PN, Ansari AA, Lockwood E, Brodie A. Spectrum of disease in macaque monkeys chronically infected with SIV/SMM. Vet Immunol Immunopathol 1989; 21: 13-24. 3. Centers for Disease Control. Guidelines to prevent simian immunodeficiency virus infection in laboratory workers and animal handlers. MMWR 1988; 37: 693-704. 4. Parekh BS, Pau C, Granade TC, et al. Oligomeric nature of transmembrane glycoproteins of HIV-2: procedures for their efficient dissociation and preparation of western blots for diagnosis. AIDS 1991; 5: 1009-13. 5. Villinger F, Powell JD, Jehuda-Cohen T, et al. Detection of occult simian immunodeficiency virus SIVsmm infection in asymptomatic seronegative nonhuman primates and evidence for variation in SIV gag sequence between in vivo- and in vitro-propagated virus. J Virol 1991; 65: 1855-62. 6. Allan JS, Short M, Taylor ME, et al. Species-specific diversity among simian immunodeficiency viruses from African green monkeys. J Virol 1991; 65: 2816-28.
7. Shen L, Chen ZW, Miller MD, et al. Recombinant virus vaccine-induced SIV-specific CD8+ cytotoxic T lymphocytes. Science 1991; 252: 440-52. 8. Kion TA, Hoffman GW. Anti-HIV and anti-anti-MHC antibodies in alloimmune and autoimmune mice. Science 1991; 253: 1138-40. 9. Kannagi M, Yetz JM, Letvin NL. In vitro growth characteristics of simian T-lymphotropic virus type III. Proc Natl Acad Sci USA 1985; 82: 7053-57.
ADDRESSES Retrovirus Disease Branch, Division of Viral and Rickettsial Diseases (R. F. Khabbaz, MD, T. Rowe, BSc, W. M. Heneine, PhD, J. E. Kaplan, MD, T. M. Folks, PhD), and Division of HIV/AIDS (C. A. Schable, MSc, J. R. George, PhD, C. Pau, PhD, B. S. Parekh, PhD, J. W. Curran, MD, G. Schochetman, PhD), Center for Infectious Diseases, Centers for Disease Control, Atlanta, Georgia, USA; Department of Veterinary Pathobiology, Ohio State University, Columbus, Ohio (M. D. Lairmore, PhD); and Delta Regional Primate Research Center, Tulane University, Covington, Louisiana (M. Murphey-Corb, PhD). Correspondence to Dr Rima F. Khabbaz, Retrovirus Diseases Branch, MS-G03, Centers for Disease Control, 1600 Clifton Road, Atlanta, Georgia 30333, USA.
Acquired immunodeficiency without evidence of infection with human immunodeficiency virus types 1 and 2
There have been three published cases of acquired immunodeficiency in which no evidence for infection with human immunodeficiency virus (HIV) types 1 and 2 was found. We have identified five other individuals, from the New York City area (four who have known risk factors for HIV infection), with profound CD4 depletion and clinical syndromes consistent with definitions of the acquired
immunodeficiency syndrome (AIDS) or AIDSrelated complex. None had evidence of HIV-1, 2 infection, as judged by multiple serologies over several years, standard viral co-cultures for HIV p24 Gag antigen, and proviral DNA amplification by polymerase chain reaction. There have been three reports suggesting that novel transmissible agents are associated with acquired immunodeficiency disorders. Cases include Kaposi’s sarcoma and varying degrees of immunodeficiencyl in a homosexual manKaposi’s sarcoma and Pneumocystis carinii pneumonia in a homosexual man with pronounced CD4 cell depletion,33 and Kaposi’s sarcoma and disseminated Mycobacterium tuberculosis in a heterosexual, man with a CD4 count of 120/1. In all these patients, there was no evidence for infection with human immunodeficiency virus (HIV) types 1 and 2 by serological and molecular techniques, including DNA amplification by polymerase chain reaction (PCR). We now report five other HIV-1, 2 seronegative individuals from the New York City area (four with known risk factors for HIV) who have profound CD4 depletion and clinical evidence of immune deficiency consistent with clinical descriptions of the acquired immunodeficiency /
In conclusion, large doses of vitamin A delivered every 6 months may not be sufficient to ameliorate deficiency in some settings, perhaps as a result of other dietary deficits. Conversely, the differences in outcomes between trials may be related to severity of deprivation and burden of disease: mortality rates were higher at the sites where vitamin A was effective. Further investigation of factors that modify the efficacy of vitamin A supplementation on mortality is needed to guide policy formulation. In accordance with findings in other developing countries, Sudanese children living in poor and unsanitary environments, younger children, and those sick, stunted, wasted, or consuming diets low in vitamin A were at a significantly higher risk of dying. There were differences in mortality associated with dietary intake of vitamin A even after controlling for indicators of socioeconomic status and sanitary conditions of the home. A reduction in poverty, improvements in sanitation, and access to adequate diets should remain the goals of child survival efforts. Assuring adequate levels of intake of vitamin A by increasing dietary intake through fortification of staple foods or by providing small supplementary doses frequently may be more effective in some settings than distribution of massive doses of vitamin A. Improvement of vitamin A intake by whatever possible and effective means, including periodic distribution of large doses, continues to be of high priority in areas where the deficiency is prevalent and nutritional blindness a common and tragic occurrence.
Center for Health Statistics, November 1977. (DHEW
13.
14.
publication [PHS] 78-1650). Singer JD, Willett JB. Modeling the days of our lives: using survival analysis when designing and analyzing longitudinal studies of duration and the timing of events. Psychol Bull 1991; 110: 268-90. Muhilal, Permeisih D, Idjradinata YR, Muherdiyantiningsih, Karyadi D. Vitamin A-fortified monosodium glutamate and health, growth, and survival of children: a controlled field trial. Am J Clin Nutr 1988;
48: 1271-76. 15. Swaminathan MC, Susheela TP, Thimmayamma BVS. Field prophylactic trial with a single annual oral massive dose of vitamin A. Am J Clin Nutr 1970; 23: 119-22. 16. Gopalan C. Combating vitamin A deficiency-need for a revised strategy. In: Recent trends in nutrition. Proceedings of First International Symposium of the Nutrition Foundation of India. Oxford: Oxford University Press, 1991 (prefatory chapter). 17. Rahmathullah L, Underwood BA, Thulasiraj RD, Milton RC. Diarrhea, respiratory infections, and growth are not affected by a weekly low-dose vitamin A supplement: a masked, controlled field trial in children in southern India. Am J Clin Nutr 1991; 54: 568-77. 18. Glover J. Factors affecting vitamin A transport in animals and man. Proc Nutr Soc 1983; 42: 19-30. 19. Udomkesmalee E, Dhanamitta S, Sirisinha S, et al. Effect of vitamin A and zinc supplementation on the nutriture of children in Northeast Thailand. Am J Clin Nutr 1992; 56: 50-57.
SHORT REPORTS Simian immunodeficiency virus needlestick accident in a laboratory worker
We thank Dr Walter Willett and Dr John Orav for valuable advice throughout the study, Dr El Fatih El Samani for help in the planning and early phases of the project, the USAID mission in Khartoum for their invaluable support, the field staff whose hard work made the study possible, Dr Elizabeth Allred for her assistance in data management, Hoffinan-La Roche Task Force Sight and Life Program for provision of vitamin capsules and for conducting the assays, and Ms Jill Arnold for her assistance in the preparation of the manuscript.
This study was carried out under cooperative agreement No. DAN-0045G-SS-6067 of the Office of Nutrition, US Agency for International Development (USAID), Washington, DC, and the Harvard Institute for International Development, Cambridge, MA, USA, and the Division of Nutrition, Ministry of Health, Khartoum, Sudan.
REFERENCES 1. Sivakumar B, Reddy V. Absorption of labelled vitamin A in children during infection. Br J Nutr 1972; 27: 299-304. 2. Barclay AJG, Foster A, Sommer A. Vitamin A supplements and mortality related to measles: a randomized clinical trial. BMJ 1987;
294: 294-96. Klein M. A randomized, controlled trial of vitamin A in children with severe measles. N Engl J Med 1990; 323: 160-64. 4. Sommer A, Hussaini G, Tarwotjo I, Susanto D. Increased mortality in children with mild vitamin A deficiency. Lancet 1983; ii: 585-88. 5. Sommer A. Mortality associated with mild, untreated xerophthalmia. Trans Am Ophth Soc 1983; 81: 825-53. 6. Sommer A, Djunaedi E, Loeden AA, et al. Impact of vitamin A supplementation on childhood mortality. Lancet 1986; i: 1169-73. 7. Vijayaraghavan K, Radhaiah G, Prakasam BS, Sarma KVR, Reddy V. Effect of massive dose vitamin A on morbidity and mortality in Indian children. Lancet 1990; 336: 1342-45. 8. West KP Jr, Pokhrel RP, Katz J, et al. Efficacy of vitamin A in reducing preschool child mortality in Nepal. Lancet 1991; 338: 67-71. 9. Rahmathullah L, Underwood BA, Thulasiraj RD, et al. Reduced mortality among children in southern India receiving a small weekly dose of vitamin A. N Engl J Med 1990; 323: 929-35. 10. United States Department of Health, Education and Welfare, Public Health Service, and the Food Composition and Planning Branch of the Food and Agricultural Organization. Food composition tables for use in Africa. Rome: FAO, 1968. 11. United States Department of Agriculture, Agricultural Research Service. Composition of foods, Agriculture Handbook No. 8-1. Washington, 3.
Hussey GD,
DC, USDA, November, 1976. 12. Hamill PVV, Drizd TA, Johnson CL, et al. NCHS growth curves for children birth-18 years United States. Hyattsville, MD: National
The macaque monkey infected with simian immunodeficiency virus (SIV) is an animal model of the acquired immunodeficiency syndrome. We investigated a laboratory worker who was exposed by needlestick accident to blood from an SIVinfected macaque. Seroreactivity to SIV developed within 3 months of exposure, with antibody titres peaking from the third to the fifth month and declining thereafter. Polymerase chain reaction for SIV sequences and cultures of peripheral-blood mononuclear cells failed to show infection. Inoculation of an SIV-negative monkey with blood from the worker did not cause infection. Animal-care and laboratory workers should adhere strictly to recommended procedures to avoid accidental exposures when working with SIV-infected animals or
specimens.
virus (SIV) infection of valuable animal model for the study of the acquired immunodeficiency syndrome (AIDS).12 There is a potential risk that human beings working in research laboratories may be exposed to SIV.3 To date, however, no SIV infection in human beings has been reported. We Simian
immunodeficiency
macaques is
a
272
SEROLOGICAL ASSAYS OF SERIAL BLOOD SAMPLES FROM LABORATORY WORKER
1 =who)e-v!rus EIA (Genetic Systems), 2=peptide EIA (Genetic Systems), 3=peptide EIA (Pharmacia) ; 4=western blot with HIV-21888 strain as a source of antigen, 5=wholevirus EIA with SIV sm/Delta/B670 antigen; 6=recombinant protein-based EIA with Baculovirus-expressed SIV mac rGP140; 7 = recombinant protein-based EIA with Baculovirus-expressed SIVmac rGP110; 8=peptide EIA with a 31-aminoacid peptide from the transmembrane prctein of S]Vmac26l (amlnoacids 600-630), 9=western blot with SIVsm/Delta B670 antigen; and 10= RIPA with SIVmac251 lysate. *1 week before the accident.
report exposure of a laboratory worker to SIV by needlestick injury and describe the subsequent follow-up. In March, 1990, a technician in a research laboratory was pricked with a blood-contaminated needle while attempting to disconnect the vacutainer sleeve from the needle after taking blood from an anaesthetised SIVsm/Delta/B670-infected macaque. The animal had been inoculated with SIV 6 months earlier, had seroconverted, was SIV culture positive, and was substantially wasted. The needle, visibly contaminated with blood, penetrated a latex glove and produced a deep puncture wound and bleeding of the worker’s thumb. She immediately scrubbed the wound with povidoneiodine followed by 10% bleach. Inflammation and swelling developed at the wound site and persisted for several weeks. The technician reported no risk behaviour for human immunodeficiency virus (HIV) infection. She did not have any illness suggestive of acute retroviral infection and remained well with no clinical or laboratory evidence of immunodeficiency.
Serum samples collected 1 week before the accident, 1 week after the accident, monthly over the following 12 months, and 19 months after the accident showed no reactivity to HIV-1 by peptide enzyme immunoassay (EIA) (Genetic Systems, Seattle, USA) or by western blot (Ortho Diagnostics, Raritan, New Jersey, USA), and no reactivity to HIV-2 or SIV by whole-virus EIAs (table). By contrast, serum samples collected from June, 1990, to March, 1991, were reactive to several synthetic peptides derived from the transmembrane region of SIV and HIV-2 (table). Peptide EIA showed that antibody titre to a 31-aminoacid peptide from the transmembrane protein of SIVe25l peaked between June and August, 1990. HIV-2 western blots with HIV -21888 as a source of antigen4 (figure, panel A) showed antibodies to envelope peptide gp41 starting in July, 1990, and a weak reactivity to p26 (also called p27) in all the samples including the pre-accident sample (table). However, SIV western blots (figure, panel B) were negative for antibody in serum samples taken from March to June, 1990, and only weakly positive for p27 (gag) after July, 1990 (table). Radioimmunoprecipitation assay (RIPA) with 35Slabelled SIVmac/251-infected cells showed reactivity to the envelope protein gpl30 in serum samples from August onwards with peak intensity in the August sample (table). 1 month after the accident and monthly thereafter for 1 year, 2 x 107 peripheral-blood mononuclear cells (PBMCs) from the worker--separated by Ficoll-Hypaque gradient centrifugation-were cultured with phytohaemagglutinin.
cultures and co-cultures with normal human PBMCs were maintained for 4 weeks and examined every 3 days; no cytopathic effect was seen. Culture supernatants were negative for SIV antigen by an SIV p27 antigencapture assay (Coulter, Hialeah, Florida, USA). Cultured cells (22 day) from February, 1991, were also negative for SIV by the polymerase chain reaction (PCR). PCR amplification was done in 2 different laboratories with primers and probes from the gag5 and pol!’ region of SIV with nested amplification in pol, and with pol, L TR, and env nested primers representing consensus sequences of HIV-2 and SIV.6 SIV mac-infected and/or SIV sm/Delta/B670infected cells, including PBMCs from infected monkeys,
Primary
Western blot of exposed worker’s sera with HIV-2 antigen (strain CDC1888, panel A) and SIV antigen (panel B). Lane 1 = pre-accident serum; lanes 2 to 13 =monthly serum samples from March, 1990, to February, 1991, lane 14= negative control; lane 15= HIV-2-positive control
273
used
positive controls. Amplified products were Southern blot hybridisation with 32P-endprobed by labelled internal oligomers. PBMCs from April to September, 1990, and from December, 1990 to March, 1991, were all negative for PCR evidence of SIV. 13 months after the accident, 10 ml of blood from the worker was inoculated into a healthy, SIV-negative young Rhesus imulata macaque. The monkey was bled every 2 weeks or monthly for 10 months after inoculation; serum samples were negative for antibodies to SIV by whole-virus EIA and by synthetic peptide EIAs, and the animal showed no evidence of SIV infection by PCR. This is, to our knowledge, the first report of a person who, after percutaneous exposure to SIV-infected macaque blood, showed evidence of seroconversion with antibodies to both gag and envelope proteins within months of exposure. Efforts to isolate virus from peripheral blood and to find SIV provirus by PCR were unsuccessful. In addition, we failed to transmit SIV by inoculating a macaque with the worker’s blood. These negative results, coupled with declining antibody titres to the SIVtransmembrane-derived peptide after a peak at 3-5 months postexposure, suggest that the subject has not become persistently infected with SIV. It is unclear whether the observed serological response is an immune response to viral proteins from inoculation of the SIV-infected macaque’s blood (a vaccination-like effect)7 or an allotypic or xenotypic response to cellular antigenic determinants in the monkey cells with crossreactivity to SIV antigens.8 The time between exposure and first detection of any response does not accord with a passive transfer of antibody. Since human PBMCs can be infected with SIV,9 the observed seroreactivity without demonstrable infection in this worker is sobering. Whole-virus EIAs were less sensitive than peptide-based EIAs, SIV western blots, and RIPA in detecting seroreactivity. Systematic and intensive investigation of individuals exposed to SIV should reveal the incidence of seroconversion. Moreover, surveillance with the sensitive assays we used is needed to effectively evaluate the risk of SIV transmission to exposed workers. This report is a reminder for those working with SIV-infected animals to be cautious and to adhere strictly to recommended procedures to minimise accidental exposures.3 were
as
We thank Dr Harold Jaffe for critical review of the manuscript John O’Connor for editorial assistance.
and Mr
REFERENCES 1.
Murphey-Corb M, Martin LN, Rangan SR, et al. Isolation of an HTLV-III related retrovirus from macaques with simian AIDS and its possible origin in asymptomatic mangabeys. Nature 1986; 321: 435-37. 2. McLure HM, Anderson DC, Fultz PN, Ansari AA, Lockwood E, Brodie A. Spectrum of disease in macaque monkeys chronically infected with SIV/SMM. Vet Immunol Immunopathol 1989; 21: 13-24. 3. Centers for Disease Control. Guidelines to prevent simian immunodeficiency virus infection in laboratory workers and animal handlers. MMWR 1988; 37: 693-704. 4. Parekh BS, Pau C, Granade TC, et al. Oligomeric nature of transmembrane glycoproteins of HIV-2: procedures for their efficient dissociation and preparation of western blots for diagnosis. AIDS 1991; 5: 1009-13. 5. Villinger F, Powell JD, Jehuda-Cohen T, et al. Detection of occult simian immunodeficiency virus SIVsmm infection in asymptomatic seronegative nonhuman primates and evidence for variation in SIV gag sequence between in vivo- and in vitro-propagated virus. J Virol 1991; 65: 1855-62. 6. Allan JS, Short M, Taylor ME, et al. Species-specific diversity among simian immunodeficiency viruses from African green monkeys. J Virol 1991; 65: 2816-28.
7. Shen L, Chen ZW, Miller MD, et al. Recombinant virus vaccine-induced SIV-specific CD8+ cytotoxic T lymphocytes. Science 1991; 252: 440-52. 8. Kion TA, Hoffman GW. Anti-HIV and anti-anti-MHC antibodies in alloimmune and autoimmune mice. Science 1991; 253: 1138-40. 9. Kannagi M, Yetz JM, Letvin NL. In vitro growth characteristics of simian T-lymphotropic virus type III. Proc Natl Acad Sci USA 1985; 82: 7053-57.
ADDRESSES Retrovirus Disease Branch, Division of Viral and Rickettsial Diseases (R. F. Khabbaz, MD, T. Rowe, BSc, W. M. Heneine, PhD, J. E. Kaplan, MD, T. M. Folks, PhD), and Division of HIV/AIDS (C. A. Schable, MSc, J. R. George, PhD, C. Pau, PhD, B. S. Parekh, PhD, J. W. Curran, MD, G. Schochetman, PhD), Center for Infectious Diseases, Centers for Disease Control, Atlanta, Georgia, USA; Department of Veterinary Pathobiology, Ohio State University, Columbus, Ohio (M. D. Lairmore, PhD); and Delta Regional Primate Research Center, Tulane University, Covington, Louisiana (M. Murphey-Corb, PhD). Correspondence to Dr Rima F. Khabbaz, Retrovirus Diseases Branch, MS-G03, Centers for Disease Control, 1600 Clifton Road, Atlanta, Georgia 30333, USA.
Acquired immunodeficiency without evidence of infection with human immunodeficiency virus types 1 and 2
There have been three published cases of acquired immunodeficiency in which no evidence for infection with human immunodeficiency virus (HIV) types 1 and 2 was found. We have identified five other individuals, from the New York City area (four who have known risk factors for HIV infection), with profound CD4 depletion and clinical syndromes consistent with definitions of the acquired
immunodeficiency syndrome (AIDS) or AIDSrelated complex. None had evidence of HIV-1, 2 infection, as judged by multiple serologies over several years, standard viral co-cultures for HIV p24 Gag antigen, and proviral DNA amplification by polymerase chain reaction. There have been three reports suggesting that novel transmissible agents are associated with acquired immunodeficiency disorders. Cases include Kaposi’s sarcoma and varying degrees of immunodeficiencyl in a homosexual manKaposi’s sarcoma and Pneumocystis carinii pneumonia in a homosexual man with pronounced CD4 cell depletion,33 and Kaposi’s sarcoma and disseminated Mycobacterium tuberculosis in a heterosexual, man with a CD4 count of 120/1. In all these patients, there was no evidence for infection with human immunodeficiency virus (HIV) types 1 and 2 by serological and molecular techniques, including DNA amplification by polymerase chain reaction (PCR). We now report five other HIV-1, 2 seronegative individuals from the New York City area (four with known risk factors for HIV) who have profound CD4 depletion and clinical evidence of immune deficiency consistent with clinical descriptions of the acquired immunodeficiency /
