No new cases of plague outbreak have been reported in Madagascar in the past ten days, and the numbers have stabilised in many districts which have previously reported active cases.
The National Institute of Communicable Diseases (NCID) on Tuesday briefed the media in Johannesburg on developments about the plague outbreak in Madagascar.
NCID Deputy Director, Professor Lucille Blumberg, said the plague is being controlled and interventions seem to be working.
Madagascar is currently experiencing a plague outbreak, and about 1 300 suspected, probable and/or confirmed cases were reported between August and October this year.
At least about 93 people have died, according to a situation report released by the World Health Organisation (WHO) on Thursday.
Blumberg said a pneumonic plague has been dominant as compared to a seasonal plague that is usually experienced in Madagascar.
Madagascar is the only African country that still experiences annual plague outbreaks when compared to other countries.
Three main types of plagues
Blumberg's colleague, Professor John Frean, said there are three main types of plagues that affect the human race which include bubonic plague, septicaemic plague and pneumonic plagues.
The bubonic plague is spread by being bitten by an infected rat flea. The patient will present with sudden onset of fever, chills, headache, weakness and swelling of glands draining the area of the bite. The patient may also complain of abnormal pain, nausea, vomiting and diarrhoea.
If treatment is commenced, symptoms usually resolve within three to five days. If not treated, the disease becomes more severe and complications may occur including septicaemic plague and pneumonic plagues, which are often fatal.
Septicaemic plague may present as a complication of untreated bubonic plague or as the first presentation of plague. Its symptoms include those of bubonic plague plus extreme weakness, abdominal pain, shock, and possibly bleeding into the skin and other organs.
Skin and other tissues may turn black and die, especially on fingers, toes, and the nose.
Pneumonic plague can result from untreated bubonic or septicaemic plague, but can also develop after inhaling infectious droplets from an infected individual. It is characterised by fever, headache, weakness, and rapidly developing pneumonia with shortness of breath, chest pain, cough, and sometimes bloody or watery sputum. Pneumonic plague is infectious, and is transmitted by droplet spread.
"This type of plague can be spread easily from person to person, and that is the predominant type of plague that has been occurring in Madagascar, with about 60% of cases being pneumonic plague," said Frean.
Treatment takes about a week and has proven to be effective.
Antibiotics, early treatment vital
He said the plague has been with the human race for a long time, and in the middle age there was an occurrence of Black Death Plague -- wherein a number of people became infected across Europe and spread the infection to scores of the population eventually.
In the case of the plague in Madagascar, Frean said: "It is inappropriate to use the term 'black death plague' nowadays, because we are not living in the middle ages. We have got modern antibiotics which can eminently treat the plague".
He said the plague is a bacterial disease and is susceptible to a range of antibiotics which are readily available and it responds to treatment if people are diagnosed early and start treatment.
"In the current outbreaks, there is no evidence that the disease is resistant to antibiotics. All the tests so far has shown that it is susceptible to the antibiotics in use."
No plague cases in SA
Blumberg said there have been no case of the plague exported from Madagascar to other countries to date.
She said there was a concern in the Seychelles where a suspected case was identified in one of the citizens who had travelled to Madagascar, but the tests that were performed excluded plague as a cause of his illness. This means that no cases of exporting the disease were reported.
"We have no plague cases in South Africa."
Blumberg said Madagascar has a number of measures in place to reduce the export of people with the plague. They have exit screening at the airport, they do temperature monitoring, they have medical staff at the airport and to date they have done very well with regards to the exit screening.
She said the WHO has moderated the risk assessment for the region, and the initial high alert has been changed from moderate to low.
Measures in place to reduce risks
"We are, however, in the region and we have a number of measures in place to reduce the risks to South Africa. Together with the exit screening at the Madagascar airport, we have entry screening in South Africa where we can test for temperatures, we have sent out guidelines on clinical presentation of plague -- when to suspect it or to test for it."
She said a South African, who visited Madagascar for the Indian Oceans Basketball championships with his three colleagues, had contracted pneumonic plague from a patient from the Seychelles [the patient eventually died].
The South African tested positive for the plague and was hospitalised and treated successfully. He recovered completely and returned to South Africa after the illness was declared adequately treated.
"He did not pose any risk to anybody. He was followed up on and he is completely well and his colleagues did not show any evidence of infection or illness. Everything was done correctly.
"There are no cases of plague in South Africa, and no exports of the disease to other countries."