Malaria infections are randomly distributed in diverse holoendemic areas of Papua New Guinea.

Mehlotra, Rajeev K.; Kasehagen, Laurin; Baisor, Moses; Lorry, Kerry; Kazura, James W.; Bockarie, Moses J.; Zimmerman, Peter A.

doi:10.4269/ajtmh.2002.67.555

Cited by 54 publications

(81 citation statements)

References 36 publications

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“…In a series of studies from PNG that have combined LM and molecular diagnostics [29,31,32], we have found that molecular methods consistently detected significantly increased prevalence of all four malaria species of humans, with the largest increases in P. malariae and P. ovale. In these studies from three different PNG populations, the prevalence of P. falciparum and P. vivax increased between 1.6 and 3.0-fold and 2.1 and 3.4-fold, respectively, and a 2.6 to 10.9-fold increase in P. malariae prevalence was observed (LM:…”

Section: Improved Diagnosis Of P Malariae and P Ovale Infections Bymentioning

confidence: 97%

“…Detection of P. ovale by LM ranged from 0 to 0.3%, whereas LDR-FMA detected P. ovale infection in 5.2 to 15.6% of the study subjects. Overall, the majority of P. malariae and P. ovale diagnoses have been observed in the context of mixed infections with P. falciparum and/or P. vivax, including several quadruple infections [29,31,32]. Therefore, it is likely that P. malariae, P. ovale and mixed species infections are substantially more common in PNG than previously thought.…”

Section: Improved Diagnosis Of P Malariae and P Ovale Infections Bymentioning

confidence: 99%

“…Moreover, mixed infections are either randomly distributed [31,32] or there might be a short age of LM-detected mixed infections [28]. Apart from differences in a wide range of ecological factors (such as climate and Anopheline vector species), these contrasting observations in P. malariae epidemiology could be linked to the virtual absence of Plasmodium vivax infections in many African populations because of the lack of the Duffy blood-group-antigen, which P. vivax requires to invade red blood cells [33].…”

Section: Variation In Parasite Prevalencementioning

confidence: 99%

“…These assays enable detection of the four Plasmodium parasite species that infect humans at densities ~100 times lower than the limit of LM detection [47] and have evolved from simple species-specific amplification strategies to multiplex approaches that incorporate semiquantitative assessments [31,[49][50][51][52][53][54][55][56]. We have greatly extended the potential use of PCR diagnosis for a wide range of epidemiological studies through our recent efforts to develop a ligase detection reaction fluorescent microsphere assay (LDR-FMA) [52,57] to evaluate all four malaria parasites of humans in a single-well multiplex format.In a series of studies from PNG that have combined LM and molecular diagnostics [29,31,32], we have found that molecular methods consistently detected significantly increased prevalence of all four malaria species of humans, with the largest increases in P. malariae and P. ovale. In these studies from three different PNG populations, the prevalence of P. falciparum and P. vivax increased between 1.6 and 3.0-fold and 2.1 and 3.4-fold, respectively, and a 2.6 to 10.9-fold increase in P. malariae prevalence was observed (LM:…”

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confidence: 97%

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Plasmodium malariae and Plasmodium ovale – the ‘bashful’ malaria parasites

Müeller

Zimmerman

Reeder

2007

Trends in Parasitology

264

245

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Although Plasmodium malariae was first described as an infectious disease of humans by Golgi in 1886 and Plasmodium ovale identified by Stevens in 1922, there are still large gaps in our knowledge of the importance of these infections as causes of malaria in different parts of the world. They have traditionally been thought of as mild illnesses that are caused by rare and, in case of P. ovale, short-lived parasites. However, recent advances in sensitive PCR diagnosis are causing a re-evaluation of this assumption. Low-level infection seems to be common across malaria-endemic areas, often as complex mixed infections. The potential interactions of P. malariae and P. ovale with Plasmodium falciparum and Plasmodium vivax might explain some basic questions of malaria epidemiology, and understanding these interactions could have an important influence on the deployment of interventions such as malaria vaccines. Geographical distributionAlthough distribution of Plasmodium malariae infection is reported as being patchy, it has been observed in all major malaria-endemic regions of the world [1]. P. malariae infections are most common in sub-Saharan Africa and the southwest Pacific, where age-specific prevalence in mass blood surveys have exceeded 15-30% [2][3][4][5][6][7][8]. By contrast, when P. malariae has been detected in malaria-endemic regions of Asia [9][10][11][12], the Middle East [13], South America [14] and Central America [15], it is observed as an infrequent infection, with blood-smear light microscopy (LM) prevalence rarely exceeding 1-2%. Much higher levels of infection were, however, found in montagnard refugees from the Cambodian-Vietnamese border [16]. In South America, P. malariae is thought to be a zoonotic infection because the genetically identical Plasmodium brasilianum infects new-world monkeys [17] and both monkeys and humans in endemic areas show high levels of seropositivity to P. malariae and P. brasilianum antigens [18].Plasmodium ovale was thought to have a much more limited distribution, with endemic transmission traditionally described as being limited to areas of tropical Africa, New Guinea, the eastern parts of Indonesia and the Philippines [19,20]. Infections with P. ovale, however, have also been reported in the Middle East [13], the Indian subcontinent [21] and different parts of Southeast Asia [11,22,23]. In West Africa (and to a lesser extent Central Africa), age specific LM prevalence of >10% have been observed [3,6] places where P. ovale is observed, it is relatively uncommon and its prevalence (as detected by LM) rarely exceeds 3-5% [22,[24][25][26].Indepth descriptions of the epidemiology of both infections based upon LM data are, thus, restricted almost exclusively to highly endemic areas in Africa and the Southwest Pacific. Detailed epidemiological studies from South America and Asia are lacking. Variation in parasite prevalenceIn West Africa, P. malariae prevalence has been reported to peak at ages similar to those of P. falciparum (i.e. in children under ten years of...

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Section: Improved Diagnosis Of P Malariae and P Ovale Infections Bymentioning

confidence: 97%

Section: Improved Diagnosis Of P Malariae and P Ovale Infections Bymentioning

confidence: 99%

Section: Variation In Parasite Prevalencementioning

confidence: 99%

mentioning

confidence: 97%

See 2 more Smart Citations

Plasmodium malariae and Plasmodium ovale – the ‘bashful’ malaria parasites

Müeller

Zimmerman

Reeder

2007

Trends in Parasitology

264

245

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“…All these samples were obtained from the West Atlantic sub-group of the Niger-Congo linguistic group of individuals, implying that all these West African individuals belong to the same ethnicity. Blood samples from PNG (n=153) were collected from the Wosera area of East Sepik Province as a part of the malaria epidemiology study previously described [25]. Samples from PNG were obtained from the Abelam linguistic group of individuals.…”

Section: Methodsmentioning

confidence: 99%

Prevalence of UGT1A9 and UGT2B7 nonsynonymous single nucleotide polymorphisms in West African, Papua New Guinean, and North American populations

Mehlotra

Bockarie

Zimmerman

2006

Eur J Clin Pharmacol

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Objective-UDP-glucuronosyltransferases (UGTs) UGT1A9 and UGT2B7 are involved in the metabolism of antimalarial dihydroartemisinin and antiretroviral zidovudine. Our aim was to analyze the prevalence of UGT1A9 (chromosome 2) and UGT2B7 (chromosome 4) nonsynonymous single nucleotide polymorphisms (SNPs) in West African (WA), Papua New Guinean (PNG), and North American (NA) populations.Methods-Using a post-PCR ligation detection reaction-fluorescent microsphere assay, frequencies of UGT1A9 (8G>A, 98T>C, 766G>A) and UGT2B7 (211G>T, 802C>T, 1192G>A) SNPs were determined in WA (n=133, 5 countries), PNG (n=153), and NA (n=350, 4 ethnic groups) individuals.Results-The UGT1A9 variant alleles were not common in the study populations. None of the SNPs were present in WA and PNG. Among NA, all 3 SNPs were present (1% each) in AsianAmericans, while 98T>C was present only in Caucasian-Americans (1%) and Hispanic-Americans (1%). Regarding UGT2B7 SNPs, the prevalence of 802C>T was 21% in WA, 28% in PNG, and 28-; 52% in NA. The SNP 211G>T was present only in Asian-Americans (9%) and Hispanic-Americans (2%), while 1192G>A was not present in any of the subjects. No significant linkage was observed at UGT1A9, UGT2B7, and between both the loci in any of the study populations.Conclusions-Taken together, the UGT1A9-UGT2B7 polymorphism profile in WA and PNG populations is similar to African-Americans, but different from Asian-Americans. It is important to determine if these differences, along with previously reported differences in cytochrome P450 2B6 allele frequencies, are associated with altered metabolism/ effectiveness of artemisinin drugs.

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