Genome sequencing and data analytics uncovers key, multi-drug resistant strain in growing Typhoid epidemic
Genomic researchers from the University of Liverpool and the Liverpool School of Tropical Medicine, with funding from the Wellcome Trust Sanger Institute, have uncovered a unique, multi-drug resistant strain of Typhoid fever in Malawi, Africa.
Identifying the Super-Strain H58
Recently, the team published two studies on Typhoid fever, a tropical disease that caused approximately 21 million illnesses and 222,000 deaths worldwide in 2014.
One study, published in Nature Genetics, suggests that one strain of Typhoid, named H58, which likely originated in Asia three decades ago, is quickly spreading across Africa.
Typhoid fever, according to the World Health Organization, is a systemic blood infection caused by the bacteria Salmonella Typhi. People generally develop the infection by ingesting contaminated food or water. The illness is characterized by prolonged fever, headache, nausea, loss of appetite, and constipation or diarrhea.
H58 has fully incorporated bacteria resistance into its main chromosome
Highly contagious, typhoid fever has generally been treated with antibiotics—which makes this newly identified superbug more than a bit alarming. Without treatment, as many as 20 percent of patients will die from the illness.
H58 appears to be resistant to most common antibiotics. And this is one evolving superbug. Dr. Melita Gordon, from the University of Liverpool’s Institute of Infection and Global Health says,
Importantly, the antibiotic resistance genes, which have previously been carried on a separate genetic package, have now been incorporated into the main chromosome of the bacteria itself, which is likely to make it easier for the Typhoid strain to retain these resistance genes.
Data show a battle of the Typhoid strains
The university, in partnership with the Wellcome Trust, has been monitoring bloodstream infections like Typhoid fever for nearly two decades. Data from the microbiology laboratory at the Malawi-Liverpool-Wellcome Trust Major Overseas Program indicate the Typhoid fever reached epidemic proportions in Malawi in 2011.
In a related study, published in the journal PLoS Neglected Tropical Diseases, the same group of researchers looked more closely at the genomes of the bacteria.
H58, with its evolving multi-drug resistance, is likely the cause of the surge in cases. Data show no H58 strains in the area until 2009. Prior to 2009, the local strains of S. Thypi could be treated with common antibiotics.
Beginning in 2010, numerous strains competed for dominance in Blantyre, Malawi. It appears, according to the research, that H58 emerged as the dominant strain, and has triggered a significant epidemic.
Dr. Nick Feasey, from the Liverpool School of Tropical Medicine says:
The rise of antibiotic resistance among Salmonellae in Africa is a major threat and concern. Not only does it mean that individuals cannot always be effectively treated, but it also appears to make global spread and large epidemics more likely.
With a super-strain identified, the Liverpool researchers are moving their focus to investigating the best ways to use vaccines to halt the spread of multi-drug resistant Typhoid fever in Africa and beyond.
Fear of vaccinations
Getting people to accept the vaccines, however, is another story. A report published by UNICEF about anti-vaccination fears in East Africa points to FM radio as a source of anti-vaccination rumor mongering in Uganda. Additionally, increasing Internet availability gives anti-vaccers a far-reaching platform for spreading false information. According to the report,
Fears of side effects and rumors of long term repercussions of vaccination, never entirely absent, have surfaced as vaccination programs have matured and approached their goals of polio eradication and tetanus elimination.
The near disappearance of some EPI target diseases, especially polio and, in some countries, tetanus, has raised the quite natural question “Why vaccinate?” This question has arisen just as political and religious forces opposed to government have a new tool, in the Internet, to provide support to their allegations against vaccination.
Spreading awareness of diseases, increasing health literacy, and encouraging vaccinations can be difficult when people turn to the radio or Internet for information, as the information isn’t always accurate. Culturally sensitive health literacy campaigns are required to teach people, not only about the efficacy of vaccines, but about proper hygiene and careful food preparation.
Erastus N. Kihumba, the Deputy Provincial Public Health Officer of the Central Province, Kenya states:
People may have refused – not because of the rumors – but because of the way they got the messages. They lacked education.
The UNICEF report urges public health officials to take full advantage of the media outlets, such as FM radio and specific Internet sites, which spread false information about vaccines as channels for education.
The nuviun blog is intended to contribute to discussion and stimulate debate on important issues in global digital health. The views are solely those of the author.