Enhanced yellow fever precautions advised amid outbreak
Travellers to two African countries urged to consult travel health clinics
People intending to travel to Angola are urged to seek advice from travel doctors as that country is experiencing a yellow fever outbreak, which has claimed at least 238 lives since December 2015.
A recent newsflash issued by the South African Society of Travel Medicine (SASTM) said that the Ugandan Ministry for Health has now also confirmed a yellow fever outbreak in Masaka and Kebisoni in the Rukungiri district of Uganda. This comes after Kenya announced its decision to bar Ugandans without proof of yellow fever vaccination from entering its territory.
The government of Uganda is reportedly in discussions with the World Health Organization (WHO) to explore ways of rolling out a mass vaccination programme in areas where yellow fever cases have been confirmed.
In addition a number of ‘imported’ cases, occurring in travellers who recently returned from Angola, have been reported. Nine cases were identified in China, three in the Democratic Republic of Congo, two in Kenya and one in Mauritania.
“It is standard protocol to have the compulsory yellow fever vaccination at least 10 days prior to travelling to any area where the virus is endemic, to ensure that it is effective, and Angola has recently been categorised as a higher risk country for yellow fever,” says Dr Pete Vincent of Netcare Travel Clinics and Medicross Tokai family medical and dental centre.
Yellow fever is a viral disease that is transmitted by a day-biting mosquito, and circulates between infected monkeys or humans and mosquitoes. There is no cure for the disease but there is an effective vaccine to prevent it. Yellow fever occurs mainly in the tropical parts of Africa, South America, eastern Panama in Central America as well as Trinidad in the Caribbean. The illness develops within six days of a person being bitten by an infected mosquito, and the onset is usually sudden. Fever develops with headache, body and back pains and, most often, nausea and vomiting.
In most cases, infection is not life-threatening. Around one in 15 people, however, fall ill with a second ‘toxic’ phase of the disease, which can be fatal. This second phase has many of the same symptoms of the first phase, but patients also develop a yellow complexion, or ‘yellow jaundice’, as a result of liver damage and bleeding. Severe damage to the major organs such as the liver, kidneys and heart is caused by the disease. The mortality rate is high in those who develop a severe form of the disease.
“International health regulations regarding yellow fever are clear, and travellers who have not been vaccinated may be refused entry into a country or even face quarantine under certain circumstances. Travellers who have been vaccinated against yellow fever are issued with an internationally recognised vaccination certificate for inspection by immigration officials. This strict control is maintained to ensure that both individual travellers and wider communities in their home countries are protected against outbreaks and the spread of this disease,” Dr Vincent explains.
“Foreigners without the vaccination certificate, who try to gain entry to South Africa from an area where yellow fever is prevalent, will not be allowed into the country and may be sent home. South Africans trying to re-enter the country after visiting yellow fever areas without a valid vaccination certificate also face the prospect of quarantine,” Dr Vincent adds.
The WHO has warned that babies aged younger than nine months, pregnant women and nursing mothers should avoid travelling to yellow fever areas. Where travel is necessary, vaccination should be discussed with a travel doctor.
“People with compromised immune systems, such as those who are HIV positive or are living with cancer, and the elderly are also advised to discuss their options with a travel doctor,” Dr Vincent notes.
“People who have severe allergies to chicken and egg protein, gelatine, or any other substances contained in the vaccination, are cautioned against having the yellow fever vaccine, and are accordingly urged not to travel to yellow fever areas.”
While the WHO guidelines state that a single vaccination is generally sufficient to provide lifelong protection against yellow fever, the majority of African and South American countries where yellow fever is endemic, require that patients are vaccinated every 10 years and will refuse entry unless the booster dose is reflected on the international vaccination documents. Given this situation Dr Vincent advises all travellers to consult a travel doctor to make certain whether they require a booster dose after 10 years or not.
Dr Vincent further advises travellers to take special precautions against mosquito bites, not only because there are a number of unpleasant diseases transmitted by mosquitoes, but also due to fact that the irritation these insects cause can detract from the pleasure of travel.
Steps to prevent mosquito bites:
- Apply a good-quality DEET (N,N-diethyl-m-toluamide) mosquito repellent to any exposed skin.
- If you are wearing sun protection lotion, apply mosquito repellent after the sunscreen.
- Wear long-sleeved shirts and long pants. Mosquitoes are less likely to bite on areas covered by clothing, particularly if the clothing is loose fitting.
- Protect yourself with a mosquito net while sleeping. Remember to check that there are no rips in the fabric and ensure that you do not let the fabric rest against your skin, as mosquitoes could bite you through the netting.
- Permethrin insect repellent fabric sprays are very useful to spray on collars, cuffs and the bottoms of long pants, as well as curtains, bedding and mosquito nets.