Malaria vaccine safe for children infected with HIV

Tuesday November 08 2016
Malaria vaccine

Dr Lucas Otieno Principal Investigator KEMRI/Water Reed Kombewa Clinical Research Centre, one of the three people behind the Malaria vaccine at the laboratory. PHOTO | /TOM OTIENO

A year after Mary Otieno gave birth, her baby suffered a severe bout of malaria. Doctors at the local health facility in Kisumu County in western Kenya where Ms Otieno sought help, also discovered that the baby was HIV-positive.

“That’s how I also learnt of my status,” she said.

HIV-positive children are more vulnerable to malaria attacks than those without the virus, due to their low levels of immunity.

According to the World Health Organisation, once infected with malaria, children suffer such adverse effects of the disease as severe anaemia that can cause death if it is not detected early and treated promptly. But families of these vulnerable children can now breathe a sigh of relief following new findings published in the Lancet Infectious Disease Journal stating that the new RTS,S malaria vaccine is safe to administer to children infected with HIV.

“This means that these children can also benefit from the protection that this vaccine offers against malaria,” said Dr Lucas Otieno, lead author of the study by the Kenya Medical Research Institute Walter Reed Project.

The researchers found that the vaccine is well tolerated in children with early stage HIV infection who are taking ARVs and co-trimoxazole (septrin) — the WHO recommended treatment for HIV in children.


Disease burden

The findings of the three-year study conducted in western Kenya, also showed that children vaccinated with RTS,S had fewer cases of mild and severe malaria compared with those who did not receive the vaccine.

According to the WHO, malaria is a leading cause of child deaths in sub-Saharan Africa which is home to 88 per cent of the cases and a whopping 90 per cent of global deaths due to malaria. The disease is a major cause of child mortality in East Africa — a region that is also grappling with the HIV/Aids pandemic, posing a double disease burden on the region’s health sector. HIV tends to increase the risk and severity of malaria cases among children.

Dr Otieno said that for the vaccine to fully benefit HIV infected children, East African countries should aim at ensuring all children who test positive are promptly diagnosed and put on treatment.

“Our study focused on HIV positive children who were on ARVs and septrin. So we can guarantee the safety of the malaria vaccine among children receiving HIV treatment,” said Dr Otieno.

The RTS,S vaccine — developed by Path and GlaxoSmithKline — is currently the most advanced vaccine against malaria in children.

A co-author of the study Martina Oneko said that in order to increase access to HIV treatment, there is a need to address the stigma associated with the disease.

“Due to the fear of being stigmatised, most women fail to go for tests and may not, therefore, be aware that they or their children are infected,” said Dr Oneko. “Some may also start treatment and discontinue mid-way for fear that other people will find out that the drugs they are taking and also giving their children are for HIV treatment.”

Malaria prevention

The RTS,S vaccine offers partial protection against malaria. Four doses of the vaccine offer 39 per cent protection against malaria in children (5-17 months) and 27 per cent in infants (6-12 weeks).

Therefore, to effectively fight malaria, the researchers noted that the vaccine should be used alongside other malaria prevention interventions such as insecticide-treated bed nets and indoor residual sprays.

“There’s no magic bullet against the disease. So all approaches should be embraced to effectively fight malaria,” said Dr Otieno.

The safety of the vaccine had previously been assessed among HIV negative children.

The study by Kemri Walter Reed/CDC was the first ever to specifically seek to test the safety of RTS,S among children infected with HIV.

The WHO this year called for large-scale pilot implementation studies to be carried out before countries get the nod to roll out the RTS,S vaccine for general public use.