Reports of the recent plague outbreak in Madagascar were scary. But what about other diseases and epidemics we should be looking out for?
Several infectious diseases from the past, such as the Black Death, were encouraged by factors such as climate change, unsanitary conditions and migration between continents. But what exactly are the conditions that would favour a disease outbreak in South Africa?
Current drought situation
With the drought situation in the Western Cape, there are risk factors that may lead to outbreaks of certain diseases. “The present drought and related severe water restrictions open up a pathway for the transmission of infections that may be difficult to manage should these restrictions continue for a long time,” says Dr Jo Barnes from the Department of Global Health at Stellenbosch University.
These diseases also have the tendency to get out of control and spread to other areas.
Clean water and the safe disposal of faeces and perishable foods are needed to avoid the outbreak of waterborne disease in any community.
“The factors that are the most important in determining outbreaks of communicable diseases are the quality and quantity of the water supply in a community, the sanitation facilities and standards, the quality and cleanliness of food, the climate and the vulnerabilities of the population in that area,” says Dr Barnes.
When do these diseases spread?
We have large numbers of poor people, people who do not have enough to eat and who suffer from chronic diseases, particularly conditions like HIV/Aids that compromise the immune system.
Once an infectious disease takes hold in a population living in poor conditions, the spread of that disease can be quite rapid. Another factor when considering the risks to people living under severe drought conditions is the capacity of health services to cope.
What about health services?
This is a big concern as our health services are already under serious strain. When health services are overwhelmed, diseases are able to spread unchecked. This aspect needs serious consideration, but as the area is already in the grip of a drought, it is too late to improve present access to health services. Such actions require proper planning, time and money.
So which diseases are the biggest threat?
“The most important and probably first type of outbreak that can occur most likely involves the waterborne diarrhoeal diseases. Typhoid fever is one such an example. At present the Western Cape does not have indigenous cholera but that may change, depending on environmental, climatic and human factors,” says Dr Barnes. Let’s take a look at some of these diseases that are bound to hit South Africa if drought and unsanitary conditions persist.
Giardiasis, popularly revered to as “beaver fever”, is a parasitic disease caused by Giardia lamblia. While it’s possible that the disease can live in some people without presenting any symptoms, the symptoms are largely abdominal cramps, diarrhoea, nausea and fatigue. These symptoms typically last for two weeks and can be treated, but like any infection of the digestive system, giardiasis can be dangerous especially in those with impaired immune systems.
2. Typhoid fever
Typhoid fever is caused by the bacteria Salmonella typhi and is transferred between humans. Typhoid can spread quickly and can be fatal if not treated immediately. Typhoid is a risk especially in developing countries and countries experiencing drought. The two most prominent symptoms are high fever and a rash. Other symptoms include abdominal pain and headaches.
3. Hepatitis A
Hepatitis A is an infection of the liver cells. As the body’s immune system tries to fight the virus, the response by the immune system causes liver cell damage and inflammation. According to the World Health Organization, hepatitis A occurs sporadically and often results in epidemics worldwide, and has a tendency to reoccur. Hepatitis A is spread through contaminated food and water.
While hepatitis A doesn’t cause chronic liver failure like hepatitis B and C, it can still cause acute liver failure, which is often fatal. Symptoms can range from mild to severe and can include fever, fatigue, diarrhoea, vomiting and jaundice (yellow skin).
4. Amoebic dysentery
Amoebic dysentery is an infection of the intestines caused by Entamoeba hystolitica. These can attach themselves to the gut lining and spread via the intestinal wall to other organs.
Amoebic dysentery mostly stays inside the intestines and causes bloody diarrhoea, vomiting, nausea and stomach cramps. While the symptoms can be treated and disappear after a couple of days, amoebic dysentery can be fatal if dehydration occurs, especially in those with compromised immune systems. Complications of dysentery can be severe.
5. West Nile Virus
West Nile Virus (WNV) is a mosquito-borne virus that is transmitted to horses and humans through mosquito bites. WNV has occured in South Africa before – the largest outbreak among humans was in the Karoo in 1974, with another outbreak following in the Witwatersrand area in the 1980s.
A study lead by researchers in the USA has found that drought increases the severity of WNV in the USA – a pattern of drought was the dominant weather pattern correlated with the size of a WNV epidemic, researchers say.
Symptoms include feelings of severe illness – a high fever, headache, stiff neck, disorientation, muscle weakness, numbness and paralysis.