Science
Malaria Parasitemia in Apparently Healthy Blood Donors in North-Central Nigeria James G. Damen, MSc, FMLSCN,1* Obioma Barnabas, BSc, FMLSCN,2 Dapus Damulak, MBBS, FMCpath,3 Bala D. Ntuhun, AMLSCN, FMLSCN,3 M. D. Lugos, MSc, FMLSCN,1 Bryan Nyary, MBA4 Lab Med Winter 2015;46:9-46 DOI: 10.1309/LMZ18YTESFA8PLFR
ABSTRACT Objective: To determine the prevalence of transmissible malaria in apparently healthy blood donors in the city of Jos in north-central Nigeria. Methods: We collected blood specimens from individuals who had passed the screening criteria for blood donation. We created thin and thick blood films using the blood film template provided by the World Health Organization (WHO). The films were allowed to air dry; then, we stained them using a 3% Giemsa solution and examined them microscopically. In specimens that tested positive the malaria species was identified.
in donors aged 20 years or younger (25.0%). Plasmodium falciparum was the predominant species (98.0%); the least prevalent was Plasmodium malariae (2.0%). In male donors the prevalence of malaria parasitemia was 62.0%; the prevalence in female donors was 62.5%. Among paid donors the malaria parasitemia rate was 82.3%, compared with 22.4% in volunteer donors. Donors who reported their occupation as businessperson (individual who engages in commercial trade, mostly outdoors in a market environment) had the highest prevalence, at 94.3%; students had the lowest prevalence, at 31.9%. Conclusion: A high percentage of blood donors in Jos, Nigeria, actually harbor malaria, which is cause for concern and more careful donor screening by healthcare professionals in that region is warranted.
Results: The highest prevalence of malaria was in donors aged between 31 and 40 years (65.1%), whereas the lowest prevalence was
Keywords: malaria, blood donor Plasmodium falciparum, Plasmodium malariae, blood product, parasitemia
Malaria is a major cause of morbidity and mortality in subSaharan Africa.1 Nigeria has a high prevalence of malaria; this disease is a leading cause of morbidity and mortality in the country.2 Plasmodium species, the infective agent of malaria, is transmitted to humans by infected female anopheline mosquitos. Although blood transfusion is a rare source of malaria worldwide, it may be more common in areas where malaria is endemic. Blood transfusion is
generally believed to be safe in Nigeria; however it can be a vehicle for the transmission of malaria parasites.3
Abbreviations: HIV, human immunodeficiency virus; HBsAg, hepatitis B surface antigen; WHO, World Health Organization Department of Medical Laboratory Science, University of Jos, Nigeria, Federal School of Medical Laboratory Science and 3Haematology and Blood Transfusion Services Department, Jos University Teaching Hospital, Jos, Nigeria, 4Global Health Care Consulting, Chicago, IL 1 2
*To whom correspondence should be addressed. [email protected]
42 Lab Medicine
Winter 2015 | Volume 46, Number 1
Donated blood is safer nowadays due to increased predonation testing and more stringent donor screening criteria. Various pathogens, however, are still transmitted among individuals through blood transfusions.4 The malaria parasite is an intraerythrocytic parasite that can be transmitted by transfusion of any blood component containing infected red blood cells. Transfusiontransmitted malaria often has a short incubation period compared with natural infection because the parasite has already undergone pre-erythrocytic development.5 Bloodtransmissible protozoan parasites include Trypanosoma, Leishmania, Toxoplasma, Plasmodium, and Babesia.6 Malaria is holoendemic in Nigeria. Hence, we designed and undertook this study to determine the prevalence of malaria among blood donors in our population of blood donors, with the intention of alerting the appropriate authorities to the frequency of transfusible malaria in north-central Nigeria.
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Materials and Methods We carried out this study in the Blood Bank and Transfusion Service Unit of Jos University Teaching Hospital, Jos, Nigeria, between March 2008 and September 2008. In our blood bank, screening of blood is mandatory for some infectious diseases and is undertaken routinely for prospective donors before blood is collected. Prospective donors are screened before donation for human immunodeficiency virus (HIV), syphilis, hepatitis B surface antigen (HBsAg), and hepatitis C. However, malaria is not included in the list of required transmissible infection screenings because it would be difficult to maintain an adequate blood supply if malaria-contaminated blood products were to be rejected. Also, colloquially, malaria screening is often ignored by laboratory scientists in Nigeria due to low testing capacity, usually because of lack of personnel, work overload, or test stockouts. We included 400 apparently healthy individuals (nonfebrile, nonsymptomatic, and with no self-reported malaise), representing blood donors in north-central Nigeria who had successfully met the screening criteria for blood donation. Blood specimens were collected via venipuncture.8-10 Thick and thin blood films were prepared by medical laboratory scientists according to the technique described by Cheesbrough,11 from each blood specimen on the same clean, grease-free slide using the blood film template provided by the World Health Organization (WHO). We allowed the films to air dry, stained them using a 3% Giemsa solution for 30 minutes,11 and then examined them under an oil immersion objective on a binocular microscope. For specimens in which we identified malaria parasites, we performed speciation of the malaria on the thin blood films, whereas we assessed parasite density on the thick blood films. Quality control of the smears was carried out by a WHO-certified microscopist. Using a questionnaire for each donor, study participants self-reported their demographic information, including age, sex, category of donor (commercial, relative, or volunteer), and occupation (student, civil servant, or businessperson). The health before screening of each donor was also self-reported through a questionnaire that asked basic health questions regarding presence or absence of fever, current medication use, and history of
www.labmedicine.com
hospitalization. Donors also underwent a brief physical examination. The term commercial donators refers to individuals who receive payment for donating blood. In Nigeria, if a recipient needs blood, it is the responsibility of the recipient or his or her relatives to find a donor. In some cases, this is a family member (the relative donor category); in others, the family of the recipient will seek out a donor and will pay that person for the donation (the commercial donor category). Blood products are also acquired through volunteer blood donors (the volunteer donor category). The occupation category was made up of students (who are generally educated on malaria and malaria transmission), civil servants (who spend much of their time outdoors), and businesspeople (those who engage in commercial trade, primarily in outdoor market environments, and therefore have more exposure to malaria than the individuals in the other categories).
Ethical Considerations We obtained verbal consent from the subjects before enrolling them in this study. We also obtained permission from the institutional Health Research Ethical Committee of the Jos University Teaching Hospital before beginning the study.
Results We discovered a 62.0% prevalence (248/400) of malaria parasitemia in the study specimens. Our results showed that the group of individuals aged 20 years and younger had a 25.0% prevalence for malaria parasitemia (2/8), whereas individuals aged 31 years to less than 41 years had an 65.1% prevalence (84/129) of infection (Table 1). The distribution of Plasmodium species showed a 98.0% prevalence of Plasmodium falciparum (243/248) and a 2.0% prevalence of Plasmodium malariae (5/248). Plasmodium vivax, P. ovale, or mixed infections were not found. The absence of P. vivax and P. ovale was similar to the findings of a study performed in southeastern Nigeria, which found a P. falciparum prevalence of 100% and a rate of mixed infection with P. falciparum and P. malariae of 2.3%.12
Winter 2015 | Volume 46, Number 1 Lab Medicine
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Science
Table 1. Prevalence of Malaria Parasitemia– Positive Specimens by Age of Donor No. With Age of Donor (y) No. Examined Positive Results
Prevalence (%)
Malaria Parasitemia in Apparently Healthy Blood Donors in North-Central Nigeria James G. Damen, MSc, FMLSCN,1* Obioma Barnabas, BSc, FMLSCN,2 Dapus Damulak, MBBS, FMCpath,3 Bala D. Ntuhun, AMLSCN, FMLSCN,3 M. D. Lugos, MSc, FMLSCN,1 Bryan Nyary, MBA4 Lab Med Winter 2015;46:9-46 DOI: 10.1309/LMZ18YTESFA8PLFR
ABSTRACT Objective: To determine the prevalence of transmissible malaria in apparently healthy blood donors in the city of Jos in north-central Nigeria. Methods: We collected blood specimens from individuals who had passed the screening criteria for blood donation. We created thin and thick blood films using the blood film template provided by the World Health Organization (WHO). The films were allowed to air dry; then, we stained them using a 3% Giemsa solution and examined them microscopically. In specimens that tested positive the malaria species was identified.
in donors aged 20 years or younger (25.0%). Plasmodium falciparum was the predominant species (98.0%); the least prevalent was Plasmodium malariae (2.0%). In male donors the prevalence of malaria parasitemia was 62.0%; the prevalence in female donors was 62.5%. Among paid donors the malaria parasitemia rate was 82.3%, compared with 22.4% in volunteer donors. Donors who reported their occupation as businessperson (individual who engages in commercial trade, mostly outdoors in a market environment) had the highest prevalence, at 94.3%; students had the lowest prevalence, at 31.9%. Conclusion: A high percentage of blood donors in Jos, Nigeria, actually harbor malaria, which is cause for concern and more careful donor screening by healthcare professionals in that region is warranted.
Results: The highest prevalence of malaria was in donors aged between 31 and 40 years (65.1%), whereas the lowest prevalence was
Keywords: malaria, blood donor Plasmodium falciparum, Plasmodium malariae, blood product, parasitemia
Malaria is a major cause of morbidity and mortality in subSaharan Africa.1 Nigeria has a high prevalence of malaria; this disease is a leading cause of morbidity and mortality in the country.2 Plasmodium species, the infective agent of malaria, is transmitted to humans by infected female anopheline mosquitos. Although blood transfusion is a rare source of malaria worldwide, it may be more common in areas where malaria is endemic. Blood transfusion is
generally believed to be safe in Nigeria; however it can be a vehicle for the transmission of malaria parasites.3
Abbreviations: HIV, human immunodeficiency virus; HBsAg, hepatitis B surface antigen; WHO, World Health Organization Department of Medical Laboratory Science, University of Jos, Nigeria, Federal School of Medical Laboratory Science and 3Haematology and Blood Transfusion Services Department, Jos University Teaching Hospital, Jos, Nigeria, 4Global Health Care Consulting, Chicago, IL 1 2
*To whom correspondence should be addressed. [email protected]
42 Lab Medicine
Winter 2015 | Volume 46, Number 1
Donated blood is safer nowadays due to increased predonation testing and more stringent donor screening criteria. Various pathogens, however, are still transmitted among individuals through blood transfusions.4 The malaria parasite is an intraerythrocytic parasite that can be transmitted by transfusion of any blood component containing infected red blood cells. Transfusiontransmitted malaria often has a short incubation period compared with natural infection because the parasite has already undergone pre-erythrocytic development.5 Bloodtransmissible protozoan parasites include Trypanosoma, Leishmania, Toxoplasma, Plasmodium, and Babesia.6 Malaria is holoendemic in Nigeria. Hence, we designed and undertook this study to determine the prevalence of malaria among blood donors in our population of blood donors, with the intention of alerting the appropriate authorities to the frequency of transfusible malaria in north-central Nigeria.
www.labmedicine.com
Science
Materials and Methods We carried out this study in the Blood Bank and Transfusion Service Unit of Jos University Teaching Hospital, Jos, Nigeria, between March 2008 and September 2008. In our blood bank, screening of blood is mandatory for some infectious diseases and is undertaken routinely for prospective donors before blood is collected. Prospective donors are screened before donation for human immunodeficiency virus (HIV), syphilis, hepatitis B surface antigen (HBsAg), and hepatitis C. However, malaria is not included in the list of required transmissible infection screenings because it would be difficult to maintain an adequate blood supply if malaria-contaminated blood products were to be rejected. Also, colloquially, malaria screening is often ignored by laboratory scientists in Nigeria due to low testing capacity, usually because of lack of personnel, work overload, or test stockouts. We included 400 apparently healthy individuals (nonfebrile, nonsymptomatic, and with no self-reported malaise), representing blood donors in north-central Nigeria who had successfully met the screening criteria for blood donation. Blood specimens were collected via venipuncture.8-10 Thick and thin blood films were prepared by medical laboratory scientists according to the technique described by Cheesbrough,11 from each blood specimen on the same clean, grease-free slide using the blood film template provided by the World Health Organization (WHO). We allowed the films to air dry, stained them using a 3% Giemsa solution for 30 minutes,11 and then examined them under an oil immersion objective on a binocular microscope. For specimens in which we identified malaria parasites, we performed speciation of the malaria on the thin blood films, whereas we assessed parasite density on the thick blood films. Quality control of the smears was carried out by a WHO-certified microscopist. Using a questionnaire for each donor, study participants self-reported their demographic information, including age, sex, category of donor (commercial, relative, or volunteer), and occupation (student, civil servant, or businessperson). The health before screening of each donor was also self-reported through a questionnaire that asked basic health questions regarding presence or absence of fever, current medication use, and history of
www.labmedicine.com
hospitalization. Donors also underwent a brief physical examination. The term commercial donators refers to individuals who receive payment for donating blood. In Nigeria, if a recipient needs blood, it is the responsibility of the recipient or his or her relatives to find a donor. In some cases, this is a family member (the relative donor category); in others, the family of the recipient will seek out a donor and will pay that person for the donation (the commercial donor category). Blood products are also acquired through volunteer blood donors (the volunteer donor category). The occupation category was made up of students (who are generally educated on malaria and malaria transmission), civil servants (who spend much of their time outdoors), and businesspeople (those who engage in commercial trade, primarily in outdoor market environments, and therefore have more exposure to malaria than the individuals in the other categories).
Ethical Considerations We obtained verbal consent from the subjects before enrolling them in this study. We also obtained permission from the institutional Health Research Ethical Committee of the Jos University Teaching Hospital before beginning the study.
Results We discovered a 62.0% prevalence (248/400) of malaria parasitemia in the study specimens. Our results showed that the group of individuals aged 20 years and younger had a 25.0% prevalence for malaria parasitemia (2/8), whereas individuals aged 31 years to less than 41 years had an 65.1% prevalence (84/129) of infection (Table 1). The distribution of Plasmodium species showed a 98.0% prevalence of Plasmodium falciparum (243/248) and a 2.0% prevalence of Plasmodium malariae (5/248). Plasmodium vivax, P. ovale, or mixed infections were not found. The absence of P. vivax and P. ovale was similar to the findings of a study performed in southeastern Nigeria, which found a P. falciparum prevalence of 100% and a rate of mixed infection with P. falciparum and P. malariae of 2.3%.12
Winter 2015 | Volume 46, Number 1 Lab Medicine
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Science
Table 1. Prevalence of Malaria Parasitemia– Positive Specimens by Age of Donor No. With Age of Donor (y) No. Examined Positive Results
Prevalence (%)
