Incidence of Malaria in the Interior Division of Sabah, Malaysian Borneo, Based on Nested PCR

Abstract

Introduction. Malaria is currently one of the most prevalent parasite-transmitted diseases caused by parasites of the genus Plasmodium. Misidentification of human malaria parasites especially P. knowlesi based on microscopic examination is very common. The objectives of this paper were to accurately identify the incidence of human malaria parasites in the interior division of Sabah, Malaysian Borneo, based on small subunit ribosomal RNA (ssrRNA) and to determine the misidentification rate in human malaria parasites. Methods. Nested PCR was used to detect the presence of human malaria parasites. A total of 243 blood spot samples from patients who had requested for blood film for malaria parasite (BFMP) analyses were used in this study. Results. Nested PCR findings showed that there was no P. malariae infection while the highest prevalent malaria parasite was P. knowlesi, followed by P. vivax, P. falciparum, and mixed infection. Only 69.5% of the 243 samples giving consistent nested PCR and microscopic results. Conclusion. The preliminary findings from molecular detection of malaria showed that P. knowlesi was the most prevalent Plasmodium species in the interior division of Sabah. The findings from this paper may provide a clearer picture on the actual transmission of different Plasmodium species in this region.

A Review of Plasmodium knowlesi among Macaques in Malaysia

“…introlatus was possibly be an active vector of P. knowlesi transmission in the focused regions. Similar observations were made by Joveen-Neoh et al (2011) andNaing et al (2011) at Sabah, where young adults between the age of 20 to 29 years from local forest and plantation regions were found most commonly infected with P. knowlesi.…”

Human Infections and Detection of Plasmodium knowlesi

“…All 6 were logging camp workers who had acquired their infections overseas, thereby indicating that there are no indigenous cases of P. malariae in Sarawak. The situation appears to be similar in Sabah, where the number of P. knowlesi infections detected by PCR at the Public Health Laboratory and at Universiti Malaysia Sabah greatly outnumbers those of P. malariae (30,40,41). The reports to date indicate that adults are more commonly infected than children.…”

“…Following the description of the large focus of human knowlesi malaria cases in the Kapit Division of Malaysian Borneo in 2004 (3), there have been reports of infections acquired in Kapit and other locations in Malaysian Borneo (28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43) and in Peninsular Malaysia (28,(44)(45)(46)(47). In some hospitals in Malaysian Borneo, knowlesi malaria accounts for the majority of malaria cases admitted to hospitals (29,38,43).…”

Evaluation of the Sensitivity of a pLDH-Based and an Aldolase-Based Rapid Diagnostic Test for Diagnosis of Uncomplicated and Severe Malaria Caused by PCR-Confirmed Plasmodium knowlesi, Plasmodium falciparum, and Plasmodium vivax

“…he simian parasite Plasmodium knowlesi is a common cause of human malaria in all age groups in Malaysian Borneo (1)(2)(3)(4)(5). In Sabah, Malaysia, the incidence of knowlesi malaria has increased with the control of Plasmodium falciparum and Plasmodium vivax (6) and accounts for up to 80% of malaria admissions to district hospitals (1,(3)(4)(5).…”

“…In Sabah, Malaysia, the incidence of knowlesi malaria has increased with the control of Plasmodium falciparum and Plasmodium vivax (6) and accounts for up to 80% of malaria admissions to district hospitals (1,(3)(4)(5). The geographic range of P. knowlesi corresponds to the overlapping distribution of the simian hosts and the forest-dwelling Anopheles leucosphyrus group of mosquitoes and extends across all of Southeast Asia from southern China, Taiwan, Philippines, and Indonesia to Bangladesh and eastern India.…”