The confirmation of the First case of infestation on man of larva eaten-corne (New World Screwwworm – NWS), deriving from a trip to South America, where this insect is weed. The details of how the patient has been infected and even where: the Center for the control and prevention of US diseases (CDC) and the associations of breeders report different origins. However, the case aroused a sensation for fear of an infection that seems to have come from a science fiction story. The offending insect are the larvae of the murderer (Cochliomyia hominivorax), that yes nourish meat of their unconscious guests, causing lacerations, pain until it is to death. They represent a huge risk especially for the livestock and for the breeding sector: according to what was declared by theUnited States Agriculture Agency (USDA), in Texas alone they could cause the loss of 1.8 billion dollars. The Vite Verme is a parasite not present in Italy And in Europe, but mainly in the Central and South America, from which it can reach the United States by moving cattle. There are no vaccines or drugs, but man rarely infested. The CDC recommends using insect repellents, cover wounds And wear opaque clothes if you travel in areas infested with a fly.
Who is larva eats meat and where he lives
Larva Eat-Carne, Moscow Moscow of the New World or Vite of the New World (New World ScrewwwormNWS) are frightening names to describe the Cochliomyia hominivoraxan insect obliged parasite (i.e. it necessarily needs to take advantage of a guest in order to reproduce) belonging to the Cochliomyia genre. The name is already afraid of fear: hominivorax In fact, it literally means eaten-by. It is mainly widespread in Mexico, Central and South America, with infestations in North America deriving from travel and movement of cattle, while It is not present in Europe and Italy.
The vital cycle of the worm eating meat
The females of the species depart up Over 300 eggs inside or close to open wounds of the guest, mainly animals such as livestock, pets, birds, but in some cases, such as that reported in the United States, also men. The larvae that emerge in about 12-24 hours, to mature they start feed on the flesh of your guest, But they do not stop on the surface: they have the ability to penetrate the fabrics and literally “screwing themselves” (hence the English name of “vine worm”, Screwwworm) inside the body of the unfortunate guest. The entire life cycle, from larva to adult, hard about 21 daysif they are found in temperate and humid climates, their favorites.
It is a particular type of parasitosis called myasisin which the infection is carried out by flies larvae and not from the insect itself. The infestations, if not recognized and stopped promptly, can lead to the death of the animal and, given the prolificity of the flies, they can spread to splashing oil.
Prevention against these flies is the most powerful weapon
As reported by Department of Agriculture of the United States (USDA) and from Food and Drug Administration (FDA), There is no vaccine, Nor drugs approved for the treatment of the festival and the most powerful weapon against Miai from Moscow larvae is the prevention:
- check carefully the animals that come from the countries where the Screwwwororm is infesting
- use repellents suitable and approved
- cure promptly injuries and animal ulcerations
Precisely in this regard, after the recent case of human infestation and to avoid outbreaks as happened in the past, the secretary of agriculture Brooke L. Rollins He spoke in Texas, the state with the largest number of cattle farms and therefore most worried about a possible infestation from Cochliomyia hominivoraxprojects to combat the proliferation of the New World Scarld (NWS). Among the proposed initiatives, to build a Mexico on the borders with Mexico Breeding of sterile fliesto be released on the territory in order to gradually reduce the population, as was done at the beginning of the 60s. An investment of 100 million dollars For the search for innovative strategies to combat larvae, as well as joint programs with Mexico for their eradication and to avoid migration to the United States of animals that could host the larvae eats meat.
Risks for man and how to prevent
The risk of a human infection of SCRAWWORM is very low, in the areas where it is not endemic. The deposition of egg and therefore the infestation, as for animals, takes place not only on Open woundsbut also in orifices such as mouth, nose and eyes. The activity of the larvae causes various symptoms such as injuries that do not heal over time, pain, bleedingunpleasant smell in wounds and can lead to Secondary bacterial infectionssince they leave wounds open and exposed to the infection. You notice the infections usually because you notice the larvae near the wound.
The treatment consists in removal surgical of all larvae, in order to avoid a second infection. Also in this case, the prevention It is the most powerful arrow in our Faretra. If you travel to countries where infestations are more frequent, the CDC Recommend to:
- cover any open wounds
- use clothes members who cover most of the body
- use repellents For approved insects for human use
- sleep in closed areas and with mechanical protections, type Mosquito nets.
The costs of the infestations and the benefits of the containment strategies
It is not the first match between the United States and Screwwworm. Already in 1935 An infestation of worm eaten meat caused the death of beyond the USA 180 thousand breeding animals Only in half of the Texas counties. A first solution came to the end of the Second World Warwhen they began to exploit the gamma cobalt 60 radiation to radiate and make sterile The males of the assassins of the new world.
Since then, eradication processes of the Cochliomyia hominivora First in the United States and later in nearby Mexico and Central and Southern America countries. In the United States, it is considered extinct Already starting from the second half of the 1960s, but there were subsequent infestations due to the movement of cattle from infested countries.
According to the USDA, today an infestation from worm eats meat, considering leakage of cattle, costs of drugs and work, could cause the loss of 1.8 billion dollars… Only in Texas. The value of the benefits obtained by the US zootechnical industry over the years following the eradication exceeds 900 million dollarswhile in Mexico a saving of about is estimated 2 billion dollars from the 90s to today, which arrives to 73 million dollars a year For all central America.
