Tropical Health Matters

Bright Orji, PhD, FAIPH, FAPH, President, Health Promotion and Education Alumni Association, Ibadan College of Medicine (HPEAAICM) has written a brief obituary for our colleague, Sakiru Otusanya.

Dear Colleagues,

It is with a heavy heart that I announce the passing of our friend and colleague, Mr. Sikiru Otusanya, fondly known as “Otu.”

Otu was a member of the 1998/1999 MPH set and worked with UNICEF during his career. He will be fondly remembered for his contributions to public health, particularly his work on Guinea worm eradication, as part of the broader global efforts in which Nigeria played a significant role.

In addition, Otu applied his MPH skills as an essential Front-line staff of the Carter Center supported successful Nigeria Guinea Worm Eradication Programme NIGEP through community organizing and health education. He continued his   NIGEP water and  sanitation  work after guinea worm was eliminated in Nigeria as a nation consultant for UNICEF, traveling throughout the country.

Organizing community water supply to prevent Guinea Worm

Otu was an active and financially committed member of our Alumni Association and contributed immensely to laying a strong foundation for the Association.

He passed away yesterday, Saturday, 20 December 2025, and was buried today in Ijebu Ode, in accordance with Muslim rights

Our prayers are with his wife Dupe and their children and his many friends and family in Igbo-Ora, Ijebu Ode, across the continent and global community.

He will be greatly missed.

Asymptomatic malaria poses a major challenge for the elimination of malaria especially in low transmission settings and places where the move toward elimination looks most promising. When communities and front-line health staff do not “see” malaria, the disease will persist. This holds true for falciparum as well as vivax and on all continents where malaria is prevalent. Some examples of the problem from recent publications are shared here.

Saavedra-Samillán and colleagues describe the challenge in Peru as well as the broader Amazon Region. They tested and found Plasmodium vivax most frequently using both microscopy and qPCR. Submicroscopic malaria infections were highly prevalent and most were asymptomatic. The conclusion was the need for more accurate diagnostic as well as broader surveillance methods and “better detect and control hidden malaria transmission.”

Muhye and co-researchers address the “significant challenge to malaria control and elimination efforts due to its role in sustaining silent transmission within communities” in Ethiopia. Their study revealed that “asymptomatic schoolchildren serve as significant reservoirs for malaria, challenging elimination efforts.” Also of note, these older school-aged children seem less likely to benefit from insecticide treated bed nets that their pre-school aged counterparts. Thus their findings go a step beyond identifying the problem but point to weaknesses in interventions that could prevent it.

In Tanzania, Lin et al. raised the concern that “asymptomatic malaria carriers often harbor low parasite densities missed by rapid diagnostic tests.” Using colony-reared Anopheles gambiae, they demonstrated that “parasites circulating at the limit of PCR detection commonly infect mosquitoes,” and furthermore “a small proportion of highly infectious carriers contribute disproportionately to transmission” opening opportunities for targeted intervention.

Jiram and colleagues examined “Persistent low-density infection in areas at risk of malaria reintroduction in Malaysia.” Malaysia is where Plasmodium knowlesi (zoonotic malaria) and low-density infections pose reintroduction risks in previously malaria-free areas. They note that “Asymptomatic low-density malaria infections persist in purportedly malaria-free communities, remaining undetectable by routine microscopy. These hidden parasite reservoirs pose a risk for malaria reintroduction,” and recommend more sensitive diagnostic tools for malaria surveillance programs as well as focusing interventions on the hot-spots thereby identified.

While most of the recent articles focus on Africa, we can see that asymptomatic malaria poses a global problem that threatens elimination efforts. Not only do diagnostic and surveillance efforts need to account for infections that are more difficult to detect, but intervention tools such as bed nets and immunization need to be better targeted in order to save more lives leading up to 2030 and beyond.