Behavioural pattern of leptospirosis in humans in SVG

by Dr Eric Alanzo Audain Tue, Sept 11, 2012

Part 3 of climatological influence in the epidemiology of leptospirosis in humans in SVG (continuation from part 2)

Our retrospective investigative study shows that more than 78 per cent of the reported confirmed clinical cases of leptospirosis in human in SVG (2001-2010) occurred in the male population, due to the fact that they are at the higher end of the scale, regarding persons at risk.{{more}}

Remember that we would have highlighted earlier in part 1 of these publications that this disease is a seasonal, environmental and occupational one, hence the reason our male population is mostly affected.

Within our population, more males are associated with agriculture and fisheries, workers in slaughtering areas, storerooms and water sport activities. The number of females infected with the disease is on the increase, many of whom are associated with agricultural activities. It must be appreciated that this disease extends beyond workers within the agriculture and fisheries sector; however, the level of risk for someone to acquire the disease increases with the kind of work that is being performed.

We all are prone to the development of this disease and care must be taken at all times.

During the period 2001-2010, SVG recorded a number of fatalities as a result of persons acquiring leptospirosis.

Based on the results obtained in our investigative study, the number of confirmed clinical cases of leptospirosis in humans varies within the different communities where farming is practised on a large scale. We sincerely think that a series of town hall style interactive meetings should be conducted throughout the country, due to the public health impact that this disease is silently having on our country and it’s potential socio-economic effects with special emphasis on Chateaubelair, Buccament, Kingstown, Calliaqua, Marriaqua, Cedars and Georgetown. Some of these communities have recorded a significant increase in the number of confirmed clinical cases of the disease over the period (2001-2010).

The epidemiology of leptospirosis in humans is very complicated, as a result of the large number of animals that may host and subsequently eliminate the bacteria in their urine. The infected animal (wild or domestic) may act as what is referred to as either maintenance host or Accidental host of the bacteria. The maintenance or adoptable hosts (reservoirs) are those that are infected by the disease, but do not manifest any signs and symptoms, however do have the bacteria in their kidneys, which are then constantly eliminated into the environment and so create a high level of contamination. The accidental or non-adoptable hosts are those animals (humans, horses, cattle, dogs and cats etc) that acquired the infection as a result of becoming into direct or indirect contact with the urine of infected animals. The triangular interaction (RATS-ENVIRONMENT-ANIMAL) is of vital importance when considering the epidemiological aspect of leptospirosis. The higher the population of infected RATS in our environs, jointly with the presence of favourable climatic conditions and susceptible animals (human etc), greater will be the chances for the dissemination of Leptospira. The population of RATS in our country is on the increase as a result of the availability of food. The majority of households in SVG allow food particles from the kitchen to end up in drains and the immediate surroundings and so enhances the availability of food to these rodents.

The poor sanitary condition on farms is a factor that must be taken into consideration, regarding the increase in the population of rats, since any left over food material acts as an attractive force and thus satisfies the nutritional needs of these rodents. Dogs, cats, cattle, horses and pigs, just to mention a few, are all capable of contaminating the environment with the bacteria which causes LEPTOSPIROSIS. The urine from an infected animal may contains lots of Leptospira (bacteria) that may survive in the environment only if the climatic conditions are favourable. Pet owners who feed their pets with an excessively large portion of food, particularly after 6:30 p.m. are granting indirect support to the existence of these RATS, since on most occasion these pets are unable to eat all that food at once, which is later consumed by RATS.