Better flu surveillance for Sub-Saharan Africa

Influenza surveillance in Sub-Saharan Africa could be improved and sustained if national health authorities actively participated in the process — starting with a small number of sentinel sites or hospitals specifically selected for disease surveillance, say researchers.

Researchers implementing the Strengthening Influenza Sentinel Surveillance in Africa (SISA) project selected eight Sub-Saharan African countries — Angola, Cameroon, Ghana, Nigeria, Rwanda, Senegal, Sierra Leone, and Zambia — to help improve their influenza surveillance and reporting capacities. SISA is being implemented by Agence de Médecine Préventive (AMP) in close collaboration with the WHO.

The one-year project, which ended in December 2011, helped to establish new influenza surveillance systems in Angola and Sierra Leone, and strengthened existing systems in the remaining countries.  

The researchers assessed influenza surveillance activities and helped develop country-specific protocols to enable the countries to generate good quality epidemiological surveillance data. They also trained staff at the sentinel sites, hospitals and ministries of health on influenza data collection and analysis, and on data submission to the WHO's global influenza surveillance databases.

"SISA has demonstrated that targeted external field support can successfully help countries to start new influenza surveillance systems or reinvigorate existing ones," the researchers wrote in the study, published in the Bulletin of the World Health Organisation this month (April).

"Many African countries have weak capacities to systematically measure the burden of disease of influenza," said Christoph Steffen, programme leader for influenza and respiratory viruses for the AMP.

Steffen said that although the 2009 influenza pandemic had provided an impetus to improve influenza surveillance in Africa, continent-wide surveillance of influenza-related diseases remains underdeveloped, making it difficult to determine whether the continent would benefit substantially from large-scale influenza programmes.

Steffen said, despite the short time-frame, the project achieved its objectives.

"One of the lessons is to keep the system small, but keep it running," he said, citing how Sierra Leone is now able to carry out influenza surveillance via its four sentinel sites. Steffen added the caveat that because influenza surveillance should not be started and stopped, it was necessary to start with smaller sentinel sites that could be managed sustainably over the long term.

Nicholas Ayebazibwe, an epidemiologist with the African Field Epidemiology Network, based in Uganda, who was involved in the project, said sentinel surveillance can be expensive.  

He added that, in Africa, most surveillance data is kept by ministries of health, and that Africa should do more to share relevant data with the scientific community.

Foday Dafae, manager of the National Disease Surveillance and Response at the Ministry of Health, Sierra Leone, said that the country's influenza sentinel sites have been integrated into the disease surveillance system.  

Link to the full report in the Bulletin of the World Health Organisation