World Bulletin / News Desk
Scientists have found alarming levels of the lung disease tuberculosis in Africa, Asia, Europe and Latin America that are resistant to up to four powerful antibiotic drugs.
In a large international study published in the Lancet medical journal on Thursday, researchers found rates of both multi drug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) were higher than previously thought and were threatening global efforts to curb the spread of the disease.
"Most international recommendations for TB control have been developed for MDR-TB prevalence of up to around 5 percent. Yet now we face prevalence up to 10 times higher in some places, where almost half of the patients ... are transmitting MDR strains," Sven Hoffner of the Swedish Institute for Communicable Disease Control, said in a commentary on the study.
TB is already a worldwide pandemic that in 2010 infected 8.8 million people and killed 1.4 million of them.
Drug-resistant TB is more difficult and costly than normal TB to treat, and is more often fatal.
MDR-TB is resistant to at least two first-line drugs - isoniazid and rifampicin - while XDR-TB is resistant to those two drugs as well as a powerful antibiotic type called a fluoroquinolone and a second-line injectable antibiotic.
Treating even normal TB is a long process, with patients needing to take a cocktail of powerful antibiotics for six months. Many patients fail to correctly complete treatment, a factor which has fuelled a rise in the drug-resistant forms.
Researchers who studied rates of the disease in Estonia, Latvia, Peru, the Philippines, Russia, South Africa, South Korea, and Thailand found that almost 44 percent of cases of MDR TB were also resistant to at least one second-line drug.
SPREADS THROUGH AIR
Tracy Dalton from the United States Centers for Disease Control and Prevention, who led the study, said that so far, XDR-TB has been reported in 77 countries worldwide.
"As more individuals are diagnosed with, and treated for, drug-resistant TB, more resistance to second-line drugs is expected to emerge," she said.
The spread of these drug-resistant strains was "particularly worrisome" in areas with poor healthcare resources and limited access to effective drugs, she added.
TB is a bacterial infection that destroys patients' lung tissue, making them cough and sneeze and spread germs through the air. Experts say anyone with active TB can easily infect another 10 to 15 people a year.
The World Health Organisation (WHO) predicts that more than 2 million people will contract MDR TB by 2015.
A report by non-governmental organisations in March warned that $1.7 billion shortfall in global funds to fight TB over the next five years meant 3.4 million patients would go untreated and gains made against the disease will be reversed.
In their research, Dalton and colleagues found that rates of resistance varied widely between countries.
Overall, resistance to any second-line drug was detected in nearly 44 percent of patients, ranging from 33 percent in Thailand to 62 percent in Latvia.
In around a fifth of cases, they found resistance to at least one second-line injectable drug. This ranged from 2 percent in the Philippines to 47 percent in Latvia.
XDR-TB was found in 6.7 percent of patients overall. Rates in South Korea, at 15.2 percent, and Russia at 11.3 percent, were more than twice the WHO's global estimate of 5.4 percent at that time.
"These results show that XDR-TB is increasingly a cause for concern, especially in areas where prevalence of MDR-TB is high," said Hoffner.
Cyber-attack in 2014 likely the largest data breach in history
Photographs, videos, polls, quoted tweets no longer count toward 140-character limit
2.5 million phones recalled days before Apple introduces iPhone 7
Mark Zuckerberg has vowed to continue effort to provide satellite for Africa
3.7-billion-year-old rock suggests life began soon after Earth’s formation
Facebook will target advertising to Whatsapp users but will steer clear of third party advertising content
The global seed giant Monsanto is pulling its application to introduce GMO cotton seed after a row with the Indian government, which is demanding the company share its technology with local seed companies.
Proxima b could be visited by spacecraft within next 100 years
According to Space X, the rocket “will be subject to extreme velocities and re-entry heating,” and is part of an ongoing effort to reuse rocket parts
Flaming blue fire vortexes could be used to clean up oil spills at sea
$4.8bn Ethiopian Grand Renaissance Dam prompting fears in Cairo that water could be cut off from downstream Nile nations
Israeli military concerned game could lead to locations and images of military bases being leaked
AG600 developed for use in emergency operations has max cruising speed of 500 km per hour, max flight range of 4,500 km
Vast quantities of rare gas hint at Earth’s past, could power planet’s future
Global temperatures at record highs; Arctic sea ice levels at record lows
23-year-old researcher to create computer models of brain structures in world's largest particle physics laboratory