At least 51 people have died in Angola and more than 240 infections reported due to a deadly outbreak of yellow fever that has hit the oil-rich Southern Africa nation.

The first case was reported in December last year, in Viana, an eastern suburb of Luanda, the Angolan capital, and has since spread to Huambo, Huila, Kwanza and Sul provinces, according to Al Jazeera.

In the first six weeks of its outbreak, 29 people were reported dead and more than 90 others infected, according to the country’s director of public health, Adelaide de Carvalho.

World Heath Organization (WHO) said that yellow fever has no specific treatment whose symptoms include vomiting, fatigue, severe headache, nausea and in some people it reaches toxic levels, leading to organ failure and death.

Mosquitoes in tropical parts of Africa and Amazon region in Latin America are responsible for transmission of the viral haemorrhagic disease.

This is the first epidemic to hit Africa’s third-largest economy in 30 years and has been blamed on poor sanitation that has seen piles of waste build up, providing fertile breeding ground for the yellow fever causing-mosquito.

Angolan health officials said that inadequate funding left sanitation systems in a deplorable condition and unpaid contractors have struggled to import equipment and collect waste in poor suburbs of Luanda.

Angolan health officials and WHO have been conducting countrywide vaccination campaigns in efforts to curb the outbreak and long queues have been spotted in Luanda as people line up for the yellow fever vaccine.

Nearly 1.6 million people are targeted in the capital city and so far, more than 450,000 people have been vaccinated in the urban, Carvalho told News Week.

There has also been a reported increase in malaria, chronic diarrhoea and cholera that health official have blamed on the poor waste collection systems in the Angolan capital.

The US Centers for Disease Control and Prevention (CDC) recently issued   a travel advisory to Angola as the Angolan Embassy in London gave strict health requirements to those wishing to travel to the country.

CDC recommended that all travelers aged nine months and above must receive the vaccine at least 10 days before travelling to the nation.

Those travelling to Angola must produce a yellow fever vaccination certificate upon demand at the nation’s airports and those without them will be vaccinated.

Angola lies in the yellow fever belt of Africa which is vulnerable to the yellow fever-causing mosquito and vaccination is highly recommended to avoid contacting the disease.