Maternal Health and Malaria Amongst Indigenous Populations of Indonesia

Kellogg/Kroc Undergraduate Research Grants

Final Report:

Malaria is a prevalent infectious disease that disproportionately affects pregnant women, children, the elderly, and rural populations. Indonesia is one of nine malaria-endemic countries in the South-East Asia region. The developing country is responsible for 21% of the region’s reported malaria cases and 16% of reported malaria deaths. Despite constant global elimination efforts, islands off the west coast of Indonesia still struggle to control malaria transmission rates amongst their indigenous populations.

Interventions and Previous Research
Vector control is the primary way to prevent and reduce malaria transmission. If coverage of vector control interventions within a specific area is high enough, then a measure of protection will be conferred across the community based on the intervention type. While efforts to reduce malaria transmission from indoor biting mosquito vectors have largely been successful due to the widespread distribution of two forms of vector control – long-lasting insecticide-treated nets (LLINs), and indoor residual spraying (IRS) – outdoor malaria transmission remains a major global public health challenge.  Exposure to mosquito bites outdoors represents a primary barrier to malaria elimination in many parts of the world - especially when transmission (or biting) occurs primarily in the early evening or outdoors. This residual transmission is especially problematic in high-risk populations (HRPs) such as forest workers and indigenous groups such as the ones in Sumatra. In many of these areas, even if indoor biting is the main or only source of exposure, there may not be the option to use nets because there is nowhere to hang them and surfaces like tents cannot be sprayed for IRS. Given the limited infrastructure in these usually unprotected and higher risk zones, vector control products, such as Personal Insect Repellent Kit (PIRK), that are portable, easy-to-use, long-lasting, require no external energy sources (passive), and require minimal human compliance are distributed to reduce human-vector contact and consequently malaria (and other vector-borne disease) transmission.

Faculty Mentor and Parent Project
I first learned about this issue through my research mentor, Dr. Neil Lobo. I have worked in his medical entomology lab for the past two years where I have studied malaria transmission rates, factors that affect intervention usage, and human behavioral responses to malarial interventions. This summer, I was given the opportunity to expand my position in his lab by working on my IDS capstone project. With the help of Dr. Lobo, I partnered with WARSI Indonesia, a conservation-focused non-governmental organization (NGO) to study malaria interventions in an indigenous tribe in Indonesia.

The primary objective of the WARSI parent project is to assess the degree to which the PIRK intervention product reduces and prevents outdoor transmission of mosquito-vectored malaria using entomological correlates of protection.  Their study will provide a quantitative estimate of the reduction in human-mosquito exposure in two geographically distinct areas (Indonesia and Zambia) with specific and different malaria transmission characteristics. Study sites for field testing target populations with outdoor and forest malaria transmission in areas not covered by current malaria interventions, such as the mobile, nomadic, forest-dwelling tribes in Indonesia. The tribe that we will be working with is the Suku Anak Dalam, synonymously known as the Orang Rimba or the Kubu. The PIRK product being evaluated is a formulation of a soon-to-be EPA-registered active ingredient (AI), transfluthrin. As mentioned earlier, WARSI evaluates PIRKs using entomological correlates of protection, which are as follows. The product coverage, duration, and distance of effect were tested in a semi-field setting before the start of the field trials. This study addressed intervention strategy relevant questions such as coverage required of the product, the residual efficacy of the product, and the impact on various entomological correlates including indoor and outdoor biting. Their null hypothesis was that ‘there will be no differences in mosquito landing rates (and other entomological correlates) between PIRK device-treated and untreated spaces’.

Research Question and Methodology
Alongside PIRK testing, I studied vector control methods and malaria perceptions amongst the Kubu, an indigenous population in Sumatra, Indonesia. Specifically, do women pay importance to malaria interventions after a pregnancy? How does their perception differ from before? Does the intervention have an impact on perception?

With the help of employed translators and WARSI members, I sent survey questions to the organization and received responses remotely. In an effort to understand the tribal members’ familiarity with malaria and its interventions, my questions mainly centered around the maternal state of the woman (i.e. is she pregnant or expecting to be in the future), how familiar they were with malaria (are they aware of the disease, the symptoms, and their vulnerable status), if they had received any sort of intervention method (such as insecticide-treated bed nets, PIRK, or medications), their education and occupation status, maternal health during pregnancy (do they receive supplements and other medications, do they use intervention methods more regularly when pregnant) and their perceptions about malarial interventions (do they use bed nets regularly, do they visit health clinics, do they view malaria as a serious health risk). I completed data collection around the end of July.

Out of the 39 responses I received from my WARSI field researchers, only five women were surveyed. This is due to the cultural barriers within the Kubu tribe that prevent the women from speaking to foreign strangers. Members of WARSI could only communicate through translators or through designated tribal and NGO personnel so, as a result, many of the surveys were answered by men on behalf of their wives, mothers, or daughters. Though I was initially concerned about the bias this would introduce into my data, the surveys proved to be very effective and allowed me to collect a wide range of information while still focusing on my specific research questions. My survey questions were structured to focus on facts and unchangeable information rather than opinion-based topics.

Unfortunately, because of the aforementioned cultural barriers, I was unable to interview many of the women. As a result, I was unable to gain holistic insight into the perceptions of the Kubu tribe. However, it was very clear from previous conversations and interactions with the WARSI members that the members of the Kubu tribe felt uncomfortable with foreigners implementing and testing malaria interventions in their community’s land.

Due to COVID restraints, my initial research summer plans were scrapped, which had seemed daunting at the moment. However, conducting surveys remotely gave me the opportunity to connect with indigenous tribal communities who’s only method of communication is through the NGO that works with them. If the program had not decided to go virtual, I would not have learned of this opportunity and this project would not have been possible.