TB strain with extreme resistance to drugs creates nightmare scenario

Sep 4 2006

The appearance of a deadly new strain of tuberculosis (TB) has so concerned the World Health Organisation (WHO) that an emergency meeting of health experts has been convened in Johannesburg to discuss the issue.

Paul Nunn, the coordinator of the WHO's drug-resistance unit says the new strain has created a nightmare scenario as it appears to be resistant to almost every drug in the arsenal for fighting the disease.

He says the world is on the threshold of having to fight a strain of TB that is resistant to every medicine known to science.

Tuberculosis is a contagious disease which like the common cold, is spread through the air by people who are sick with TB.

The infection in their lungs is spread when they cough, sneeze, talk or spit and propel TB germs, known as bacilli into the air.

Only a small number of these needs to be inhaled for a person to become infected.

Each person with active TB disease who is untreated will infect on average between 10 and 15 people every year; not everyone infected becomes sick and the TB bacilli can lie dormant for years.

When a person's immune system is weakened, the chances of becoming sick are greater and people with HIV infection are much more likely to develop TB.

Every second, according to the WHO, someone in the world is newly infected with TB and currently one-third of the world's population is infected with TB.

The largest number of new TB cases in 2004 occurred in South-East Asia Region, but sub-Saharan Africa has twice the number of cases.

The WHO estimates that 1.7 million deaths resulted from TB in 2004 with both the highest number of deaths and the highest mortality per capita in Africa, where HIV has led to the rapid growth of the TB epidemic and increased the likelihood of dying from TB.

The new strain was discovered by scientists earlier this year and is not only resistant to the principal anti-TB drugs, but also to many of the second-line defences.

Among the areas found to have been affected by drug-resistant TB infection are Latvia and South Africa where amongst HIV-infected patients in the Kwazulu-Natal region, 52 of the 53 people infected have died.

As an estimated 4.5 million people in South Africa have HIV the new drug-resistant TB could very well devastate the population.

The emergency meeting aims to establish measures that will lead to the rapid diagnosis of the new strain in order to treat it with the few drugs that are still effective against the strain.

The drugs are said to be expensive and are also toxic.

The meeting will include officials from WHO, the U.S. Centers for Disease Control and Prevention and the South African Medical Research Council.