Flea bites giving the chills

The Star

Tuesday, 16/07/2013

Flea bites giving the chills
BY EDWARD R. HENRY

WHILE most people are by now well aware of the disease leptospirosis caused by rats, there is another little-known health threat that hides on the rodent.

The Petaling Jaya City Council (MBPJ) Health and Environment Department is taking pro-active steps now to pre-empt any possibility of an outbreak by alerting the public to flea-borne typhus (murine typhus). It is a disease transmitted to humans through infected fleas living on rats, resulting in high fever and rash.

Department director Dr. Chitra Davi N. Vadivellu said the threat was compounded when restaurants and residential areas dumped food waste indiscriminately and enabled the rat population to thrive.

“On an average, we trap or bait close to 100 rats a month in some areas. We do this as part of pro-active measures and not based on complaints,” she said.

“Our health inspectors are focusing on education and creating awareness on this disease among restaurant operators and the public.

“We want them to ensure waste is disposed of properly. This is one way of getting rid of the rats,” she said.

Last year, MBPJ closed 29 restaurants under the Food Establishment Licensing By-laws (MBPJ) 2007 for lack of cleanliness, workers not given typhoid shots and rats and cockroaches found running around.

According to Dr. Chitra, high fever is the most common symptom from the bite of the Oriental rat flea (ORF) that carries the murine typhus bacteria.

She stressed that flea-borne typhus was not transmitted from human to human but through the flea bites.

“Endemic typhus can cause high fever for about 10 days and although rarely fatal, the victim may need to be hospitalised. Other than high fever, the person will experience chills, aches and rashes,” she said.

“Urban areas are infested with rats.

“We are worried as the rats could be carrying the Oriental rat flea, which is the principal vector, and cause murine typhus to spread.

“Rats are also the cause of leptospirosis, or what is commonly known as ‘rat urine disease’,” she added.

The Health Ministry’s disease control division recorded 3,665 leptospirosis cases in 2012, an 85.5% increase from the 1,976 cases recorded in 2010, with 69 deaths. In 2011, there were 2,268 cases with 55 deaths.

“This has led us to believe the population of rats has increased, and that in turn may lead to the spread of the disease-carrying fleas that ride on the rodents.

“ORF are small, about one to four-millimetres long, reddish-brown and flat in shape. It has no wings but its hind legs are so powerful that it can jump distances up to 200 times its body size.

“Indoors, they live under furniture, behind baseboards, under the edges of carpets, or in cracks between boards of hardwood floors. It feeds on flea dirt as well as dead skin and other organic debris. A ‘hungry’ adult flea that drops off from a rat can jump on to a host nearby and feed on the host’s blood,” said Dr. Chitra.

She said this meant that while the the fleas primarily live on rats, they could also inhabit other domestic animals and even people.

She explained that the flea got its name from the fact that its favourite hosts were rats and it was thought to have originated from central Asia.

ORF are found worldwide and most common in seaport areas.

To reduce the possibility of flea infestations, Dr. Chitra advised the public to:

• Make homes, workplaces and restaurants less attractive to rats by removing food sources, storing garbage in closed bins and eliminating nesting areas;
• Hire professional pest exterminators to inspect and, if necessary, place baits or traps; and
• Pets such as dogs and cats must be treated on a regular basis for fleas and not be allowed to roam freely.

Oriental Rat Flea (Xenopsylla cheopis)

• Dark reddish-brown
• Fleas are heavily armored, small, wingless insects with bristles and spines that help them cling on to the rats.
• A female flea can produce about 25 eggs a day for at least 3-4 weeks. It’s about half a millimeter in length and difficult to see with the naked eye.
• Eggs are laid in the rat’s nest.
• Disease: fever, headaches, chills, abdominal pain, shock, cough and difficulty in breathing, rapid shock and death if not treated early.
• Known as grubs, the larvae feed on organic matter found on the rats.
• To maximize its chances of survival, the adult flea can lie dormant for up to a year until it senses vibration, carbon dioxide and warmth.
• The life expectancy of a flea is usually 2-3 months, but could be to 1.5 years.