Chikungunya is Causing Chaos in Chad

An Aedes mosquito, the main vector of chikungunya (CDC Global Health)

The U.S. Centers for Disease Control and Prevention issued a level 1 travel alert for the African country of Chad on September 24. The alert comes as Chad has been struggling to contain an outbreak of the chikungunya virus, which has infected more than 30,000 people in the past month.

The outbreak, which was traced back to a 63-year-old farmer in late August, has quickly spread throughout the surrounding regions, with Ouaddaï Province harboring the most cases. However, cases seem to be slowing, as proactive measures are implemented to combat the virus’s main vector: the mosquito.

Chikungunya is a vector-borne virus that spreads via Aedes albopictus and Aedes aegypti mosquitoes. In the late summer months, Chad, like many African countries, experienced elevated levels of precipitation, which fueled the Aedes mosquito, allowing it to spread throughout the region. Although the mosquitoes are usually found near the wet and humid equatorial regions of Africa, they have migrated farther north, seeking refuge in water-filled containers like tires and rain barrels. This has presented an interesting challenge for Chad’s frail healthcare system. 

This arbovirus, or mosquito-spread virus, usually causes a mild fever as well as joint pain and inflammation. Although the virus is rarely fatal, one patient—a 25-year-old man with a preexisting, non-COVID comorbidity—has died. However, the virus remains highly infectious for several weeks, which could potentially prolong the outbreak. 

The World Health Organization (WHO) has taken proactive measures to ensure that the outbreak does not spread to neighboring countries. It has shipped medications including acetaminophen to the Biltine district in Ouaddaï Province, and it has sent teams to assist with treatment and diagnostic testing. Although no vaccine currently exists, the rudimentary treatment options available will help somewhat. Unfortunately, Chad’s healthcare system is experiencing a shortage of crucial medications and a backlog of diagnostic testing as the country battles the COVID-19 pandemic and the chikungunya outbreak. 

However, the WHO has adopted other, more direct measures to control the spread of chikungunya. In the past several weeks, it has spearheaded a vector control operation in hopes of eradicating the Aedes mosquito. The intra- and extra-domiciliary spraying will hopefully slow the spread of the virus, leading to complete eradication by December, as Chad enters its drier winter months. Additionally, the WHO has distributed long-lasting insecticidal bed nets, which also have the potential to reduce the risk of transmission. With nearly 240,000 Darfurian refugees in refugee camps near the infected regions, the virus may continue to spread, unimpeded by the WHO’s proactive measures.

Unfortunately, past chikungunya outbreaks in Africa have led to larger outbreaks, infecting nearly one-third to three-quarters of a country’s population. As a result, the WHO forewarned Chad’s government that the healthcare facilities are at risk of a bottleneck—thousands of people could contract COVID-19 or chikungunya, creating a public health catastrophe.