Nav: Home

Getting to zero malaria cases in zanzibar

July 10, 2019

New research led by the Johns Hopkins Center for Communication Programs, Ifakara Health Institute and the Zanzibar Malaria Elimination Program suggests that a better understanding of human behavior at night - when malaria mosquitoes are biting - could be key to preventing lingering cases. The Center for Communication Programs (CCP) is based at the Johns Hopkins Bloomberg School of Public Health.

The new study, published July 1 in Malaria Journal, found that targeting men who work and socialize outside the home in the evenings and travelers and seasonal workers who may bring malaria to the islands from mainland Tanzania could accelerate elimination of the disease.

Zanzibar has maintained malaria prevalence below one percent for the past decade, but elimination of the deadly mosquito-borne disease remains elusive, despite the widespread use of insecticide-treated bed nets and indoor spraying.

"We've seen such great progress, but it's hard to eliminate the remaining cases," says CCP's April Monroe, PhD, who led the research. "It's the typical last mile problem: Sometimes the hardest part of the journey comes at the end. To get there, we need to focus our attention now on human behavior, instead of solely on mosquito behavior as we did in the past."

The World Health Organization estimates that between 2000 and 2015, the rate of new malaria cases declined by 37 percent globally and malaria deaths fell by 60 percent, with 6.2 million lives saved. Three quarters of those gains can be attributed to interventions such as insecticide-treated bed nets and indoor spraying for mosquitoes.

But those interventions are only designed to work indoors.

For the study, Monroe and her colleagues analyzed data from 62 in-depth interviews with community members and leaders conducted in December 2016 and April/May 2017. The researchers also looked at data from night time observation of routine community activities, such as buying and selling at local shops, watching television in public spaces and socializing in small groups, as well as large-scale community events such as weddings and religious ceremonies.

The researchers found little evidence of people using protection against mosquitoes outdoors. "Participants reported that topical repellants were not widely available in the community and were only sold at shops in town," the authors noted.

As one woman who was interviewed remarked, "When you are outside, you really can't wear the bed nets, can you?"

In low-transmission settings like Zanzibar, children under five are no longer considered the population most at risk for malaria infection. They are sleeping under their nets and are typically at home or near home after dark. It is men who are often outside at night, whether working or socializing, which could put them at higher risk.

Zanzibar is made up of a series of islands in the Indian Ocean off the coast of Tanzania, where transmission of malaria is more common. Travelers from the mainland are understood to bring many of the malaria cases found in Zanzibar with them. When a mosquito bites a person infected with the parasite, it infects the mosquito which can then transmit the disease to someone else.

Seasonal workers from mainland Tanzania come to Zanzibar for a variety of reasons, including to work in the fields from planting to harvest time and they often do not have mosquito nets. Some communities in Zanzibar have instituted a process by which newcomers register with community leaders who can connect them with testing for malaria (and treatment, if need be) as well as to offer malaria prevention information. Monroe says these community-designed systems could be scaled up in other areas of Zanzibar.

There is a great opportunity to explore the use of mosquito control tools beyond nets and spraying alongside social and behavior change interventions to help address these identified gaps in malaria prevention that occur after dark, she says.

"Building on these existing systems to target interventions should be explored so as to limit both local and imported malaria cases," the authors note.

"Human behaviour and residual malaria transmission in Zanzibar: findings from in-depth interviews and direct observation of community events" was written by April Monroe, Kimberly Mihayo, Fredros Okumu, Marceline Finda, Sarah Moore, Hannah Koenker, Matthew Lynch, Faiza Abbas, Abdullah Ali, George Greer and Steven Harvey.
-end-
The work was funded by USAID and the President's Malaria Initiative under the terms of USAID/JHU Cooperative Agreement No. AID-OAA-A-14-00057 (CCP's VectorWorks project).

Johns Hopkins University Bloomberg School of Public Health

Related Malaria Articles:

Breakthrough in malaria research
An international scientific consortium led by the cell biologists Volker Heussler from the University of Bern and Oliver Billker from the Umeå University in Sweden has for the first time systematically investigated the genome of the malaria parasite Plasmodium throughout its life cycle in a large-scale experiment.
Scientists close in on malaria vaccine
Scientists have taken another big step forward towards developing a vaccine that's effective against the most severe forms of malaria.
New tool in fight against malaria
Modifying a class of molecules originally developed to treat the skin disease psoriasis could lead to a new malaria drug that is effective against malaria parasites resistant to currently available drugs.
Malaria expert warns of need for malaria drug to treat severe cases in US
The US each year sees more than 1,500 cases of malaria, and currently there is limited access to an intravenously administered (IV) drug needed for the more serious cases.
Monkey malaria breakthrough offers cure for relapsing malaria
A breakthrough in monkey malaria research by two University of Otago scientists could help scientists diagnose and treat a relapsing form of human malaria.
Getting to zero malaria cases in zanzibar
New research led by the Johns Hopkins Center for Communication Programs, Ifakara Health Institute and the Zanzibar Malaria Elimination Program suggests that a better understanding of human behavior at night -- when malaria mosquitoes are biting -- could be key to preventing lingering cases.
Widely used malaria treatment to prevent malaria in pregnant women
A global team of researchers, led by a research team at the Liverpool School of Tropical Medicine (LSTM), are calling for a review of drug-based strategies used to prevent malaria infections in pregnant women, in areas where there is widespread resistance to existing antimalarial medicines.
Protection against Malaria: A matter of balance
A balanced production of pro and anti-inflammatory cytokines at two years of age protects against clinical malaria in early childhood, according to a study led by ISGlobal, an institution supported by ''la Caixa'' Foundation.
The math of malaria
A new mathematical model for malaria shows how competition between parasite strains within a human host reduces the odds of drug resistance developing in a high-transmission setting.
Free malaria tests coupled with diagnosis-dependent vouchers for over-the-counter malaria treatment
Coupling free diagnostic tests for malaria with discounts on artemisinin combination therapy (ACT) when malaria is diagnosed can improve the rational use of ACTs and boost testing rates, according to a cluster-randomized trial published this week in PLOS Medicine by Wendy Prudhomme O'Meara of Duke University, USA, and colleagues.
More Malaria News and Malaria Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#541 Wayfinding
These days when we want to know where we are or how to get where we want to go, most of us will pull out a smart phone with a built-in GPS and map app. Some of us old timers might still use an old school paper map from time to time. But we didn't always used to lean so heavily on maps and technology, and in some remote places of the world some people still navigate and wayfind their way without the aid of these tools... and in some cases do better without them. This week, host Rachelle Saunders...
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.