Salmonella Infections
Prelims:
General Science,
Health
Mains:
GS Paper II:
Issues relating to health and human resources, Government policies and
interventions in the health sector, GS Paper III: Science & Technology, public
health
Current relevance:
Salmonella
infections require
greater public-health attention in India because their impact extends beyond typhoid
and mild gastroenteritis to potentially serious bloodstream infections.
Highlights:
Salmonella Infections:
1.
Salmonella is a group of bacteria that can cause
infections ranging from mild gastrointestinal illness to serious bloodstream
infections.
2.
Typhoid
and paratyphoid (enteric fever) are caused by Salmonella Typhi and Salmonella Paratyphi,
respectively.
3.
Non-typhoidal
Salmonella (NTS)
infections are commonly associated with gastroenteritis and food-borne
transmission.
Disease Spectrum:
1.
NTS
commonly causes diarrhoea, stomach cramps, fever and sometimes vomiting.
2.
Most
healthy individuals recover with supportive care, but in some cases the
infection can become invasive and spread into the bloodstream.
3.
Young
children, older adults and people with underlying illnesses or weakened
immunity are
particularly vulnerable to severe and potentially life-threatening infections.
4.
The
actual burden of NTS may be underestimated because many mild infections
recover without diagnostic testing.
Transmission:
1.
Both
typhoid and non-typhoidal Salmonella infections spread through the faecal-oral
route, although their sources differ.
2.
In typhoid,
humans are the reservoir, whereas NTS can originate from animals, food
and the environment.
3.
Poultry,
eggs, meat and other animal-derived foods can serve as important sources of NTS.
4.
Contamination
may occur at several stages, including farms, slaughterhouses, food
processing, transportation, storage, restaurants and household kitchens.
5.
Cross-contamination can also occur when raw meat comes into
contact with ready-to-eat food.
One Health Dimension:
1.
Salmonella
involves interconnected risks across humans, animals, food and the
environment, making it an important One Health challenge.
2.
Controlling
infection therefore requires interventions throughout the food-production
and consumption chain, rather than focusing only on infected individuals.
3.
Better
food-handler training, sanitation, refrigeration, surveillance, monitoring
and enforcement are important for reducing transmission.
4.
Gaps
in food-safety measures remain particularly relevant in the large informal
food sector.
Antimicrobial Resistance:
1.
Increasing
antimicrobial resistance (AMR) is making serious Salmonella infections
more difficult to treat.
2.
India
has experienced a major change in the resistance pattern of S. Typhi,
particularly involving fluoroquinolone resistance.
3.
The
emergence of extensively drug-resistant typhoid demonstrates how
resistance across several antibiotic classes can leave clinicians with limited
treatment options.
4.
Addressing
the problem requires appropriate rather than indiscriminate use of
antibiotics.
Diagnostic Challenges:
1.
Many
mild NTS infections remain undiagnosed because patients may recover without
undergoing testing, making the true disease burden difficult to estimate.
2.
Blood
culture is the main test for suspected typhoid and should ideally be conducted before starting
antibiotics.
3.
The
Widal test has limitations and should not be used alone to diagnose
typhoid.
4.
Accurate
diagnosis is important for determining whether antibiotics are genuinely
required and for supporting antimicrobial stewardship.
Prevention:
1.
Safe
water and sanitation
are essential for reducing faecal-oral transmission.
2.
Household
precautions include handwashing, using safe water, thoroughly cooking
poultry and eggs, proper refrigeration of perishable foods, and separating raw
meat from ready-to-eat food.
3.
Stronger
food-safety surveillance and monitoring are necessary across the entire
food chain.
4.
The
WHO recommends typhoid conjugate vaccines for children from six months of
age; however, these are not currently part of India's Universal
Immunisation Programme.
Way Forward:
1.
Strengthen
food-safety systems, sanitation, refrigeration, monitoring and enforcement,
including within the informal food sector.
2.
Improve
diagnostic practices so that infections requiring treatment are
identified accurately.
3.
Promote
antimicrobial stewardship by reserving antibiotics primarily for severe
or invasive infections and individuals at greater risk of complications.
4.
Adopt
a comprehensive One Health approach integrating human health, animal
sources, food systems and environmental factors.
5.
Prevention
should combine vaccination, safer water and sanitation, food safety and
responsible antibiotic use to reduce both infection and antimicrobial
resistance.
Source: THE HINDU - https://www.thehindu.com/sci-tech/health/why-india-needs-to-look-beyond-typhoid-to-address-the-health-burden-of-salmonella-infections/article71387815.ece