In a major cause for concern, a new strain of cholera bacterium resistant to third generation antibiotics has been found to be circulating in India

By Syed Akbar
Hyderabad:  In a major cause for concern, a new strain of
cholera bacterium resistant to third generation antibiotics has been
found to be circulating in the country.


This cholera bacterial strain contains two super bug genes, including
the notorious New Delhi Metallo beta-lactamase-1 (blaNDM-1). The other
super bug gene is plasmid-mediated beta-lactamase-1 (blaDHA-1). Thanks
to these two super bug genes, the new cholera bacterial strain (O1 El
Tor Ogawa) has developed resistance to a majority of known
antibiotics, even those of the third generation.

The blaNDM-1, discovered a couple of years ago from hospitals in New
Delhi, created ripples in the health sector worldwide. The gene was
then found in E coli strains that cause severe diarrahoea and
vomiting, and possible death if untreated. This is the first time that
doctors have found the super bug gene, blaNDM-1, in the cholera
bacterium, Vibrio cholerae.

A team of doctors led by Dr Jharna Mandal from Jawaharlal Institute of
Postgraduate Medical Education and Research (Jipmer), Puducherry,
isolated the cholera germ strain from the stools of a two-year-old
patient. It reported the findings in the journal of the Centres for
Disease Control and Prevention (CDC), USA. The team suggested that the
antimicrobial drug susceptibility profile of the bacterium should be
monitored.

“Vibrio cholerae has developed enormous capabilities to combat
antimicrobial drug effect. It possesses efflux pumps that act on
multiple classes of antimicrobial drugs and
elaborates enzymes that can nullify the impact of complex
antimicrobial drugs,” the researchers said, adding that though the new
strain would not be an issue for treatment of cholera, it would have
“other implications”.

According to them, even though fluid replacement plays a major role in
treating cholera during outbreaks, antimicrobial drugs are crucial for
controlling the disease and its spread. Antimicrobial therapy reduces
shedding of the Vibrio cholerae bacillus in faeces from more than five
days to a day or two. The drugs also reduce the volume of diarrheic
stool and the duration of illness, hastening recovery, and decreasing
the chances of disease spread.

Once the bacterium develops resistance, it makes antimicrobial therapy
ineffective. The new strain has shown resistance to antibiotics like
tetracycline and ciprofloxacin. Health care–associated networks need
to be strengthened to ensure justified and appropriate use of
antimicrobial agents to prevent emergence of super bugs, they suggested.