Avian Influenza (“Flu”)
Avian influenza is an infectious disease of birds caused by type A strains of the influenza virus. The devastating form of influenza in chickens was recognized as a distinct disease entity as early as 1878 in Italy. The isolation of an avian influenza virus in 1901 preceded the discovery of mammalian and human influenza viruses, but it was not until 1955 that it was recognized that avian and mammalian influenza viruses are closely related.
Avian influenza A viruses - subtypes
Avian species can be infected by each of the 15 HA (Haemagglutinin) and nine NA (Neura-minidase) subtypes of influenza A viruses recognized up to now, in apparently any possible combinations. To date all outbreaks of the highly pathogenic form have been caused by influenza A viruses of subtypes H5 and H7. Highly pathogenic viruses possess a tell-tale genetic “trade mark” or signature - a distinctive set of basic amino acids in the cleavage site of the HA - that distinguishes them from all other avian influenza viruses and is associated with their exceptional virulence.
Natural Host and Reservoir
The reservoir of influenza A virus is in aquatic birds, especially ducks, shorebirds and gulls. Influenza A viruses appear well adapted to wild aquatic birds that are considered to be their natural hosts, and in which disease signs rarely appear. Considerable circumstantial evidence has long suggested that wild waterfowl introduce avian influenza viruses, in their low pathogenic form, to poultry flocks, but do not carry or directly spread highly pathogenic viruses. This role may, however, have changed very recently. The die-off of more than 6000 migratory birds, infected with the highly pathogenic H5N1 virus that began at the Qinghai Lake nature reserve in central China in late April 2005, was highly unusual and probably unprecedented. Prior to that event, wild bird deaths from highly pathogenic avian influenza viruses were rare, usually occurring as isolated cases found within the flight distance of a poultry outbreak.
Susceptible Host
The host range of influenza virus is generally unpredictable. Domestic poultry including chickens and turkeys are particularly susceptible to epidemics of rapidly fatal influenza. Influenza A viruses have been isolated from humans and from several other mammalian species. Domestic swine and Humans are now considered as mixing vessel since they are susceptible to infection with both avian and mammalian viruses, thus resulting in emergence of novel subtype.
Transmission among birds
Large amounts of virus are secreted in bird droppings, contaminating dust and soil. Airborne virus can spread the disease from bird to bird causing infection when the virus is inhaled. Contaminated equipments, vehicles, feed, cages or clothing-especially shoes can carry the virus from farm to farm. The virus can also be carried on the feets and bodies of animals, such as rodents, which act as “mechanical vectors” for spreading the disease. Direct or indirect contact of domestic flocks with wild migratory waterfowl has been implicated as a frequent cause of epidemics. Live bird markets have also played an important role in the spread of epidemics.
Disease in Birds
Infection causes a wide spectrum of symptoms in birds, ranging from mild illness to a highly contagious and rapidly fatal disease resulting in severe epidemics. The later is known as “highly pathogenic avian influenza” (HPAI). This form is characterized by sudden onset, severe illness and rapid death, with a mortality that can approach 100 percent. If the birds survive for more than 48 hrs, there is cessation of egg laying, respiratory distress, lacrimation, sinusitis, diarrhea, edema of the head, face and neck and cyanosis of unfeathered skin, particularly the comb and wattles. To date, all outbreaks of the highly pathogenic form of avian influenza have been caused by viruses of the H5 and H7 subtypes. Recent research has shown that H5 and H7 viruses of low pathogenicity can, after circulation for sometimes short periods in a poultry population, mutate into highly pathogenic viruses. Low pathogenic avian influenza (LPAI) viruses cause only mild disease or asymptomatic infection.
Flu and its significance to Humans
Influenza viruses are normally highly species-specific, meaning that viruses that infect an individual species (humans, certain species of birds, pigs, horses, and seals) stay “true” to that species, and only rarely spill over to cause infection in other species. Of the hundreds of strains of Avian influenza A viruses, only four are known to have caused human infections: H5N1, H7N3, H7N7, and H9N2. In general, human infection with these viruses has resulted in mild symptoms and very little severe illness, with one notable exception: the highly pathogenic H5N1 virus.
Scenario Before 1997
Despite the warnings to the poultry industry about these viruses, only influenza A H1N1, H2N2, H3N2 viruses have caused widespread respiratory illness in humans in the 20th century including pandemics in 1918, 1957 and 1968 heralding the emergence of each human subtype respectively.
The pandemics had its first recognizable wave in the spring of 1918, with descriptions of outbreaks in the United States, Europe and Asia by the end of April. Sequence and phylogenetic analysis of the completed 1918 gene segments suggest that the haemagglutinin and neuraminidase gene segments were derived from an avian influenza source but not directly. The HA and NA gene segments of the 1918 virus have acquired a number of changes from the avian consensus that suggests to us that the precursor to the pandemic strain spent some period of time, perhaps 5 to 10 year, adapting and evolving in a mammalian host.
In 1957, the Asian pandemic virus (H2N2) had acquired the HA, NA and PB1 gene from an avian virus, while in 1968, the Hong Kong pandemic strain (H3N2) had acquired the HA and PB1 gene from an avian source, retaining the NA from the preceding H2N2 subtype. The mechanism of emergence of subtypes in 1957 and 1968 (Reassortment of genes with avian influenza virus) is different from its first pandemic 1918.
Thus pandemic strains possessing novel HA derived from avian or animal influenza viruses, with or without other accompanying avian virus genes, sporadically emerge in humans and have the potential to cause a pandemic of influenza if the virus is capable of transmitting among a human population that lacks immunity to the novel HA. Indeed, reassortment viruses, harbouring a combination of avian and human viral genomes have been responsible for major pandemics of human influenza.
Mixing vessel
Swine have long been considered a likely mixing vessel in which avian and human viruses may reassort, since these animals possess respiratory epithelium that bear cell surface sialyloligosacharides that are preferentially recognized by avian (sialic acid (SA) a 2,3 galactose) and human influenza viruses (SA a 2, 6 galactose). Largely because of these differences in receptor specificity, avian influenza viruses were not considered to be able to directly infect humans and cause influenza like respiratory illness.
Scenario after 1997
However in the late 1990’s two subtypes of avian influenza emerged that caused respiratory infections in humans. In 1997, a high pathogenicity avian H5N1 influenza virus circulated among poultry on farms and in retail markets in Hong Kong. The H5N1 viruses were transmitted to humans, causing 18 documented cases of respiratory disease, including six deaths. In 1998-99, a second influenza A virus subtype, H9N2, was isolated from humans with respiratory disease.
This event established for the first time that these avian influenza viruses were to be considered a risk to public health. The relatively high rates of H5 and H9 antibody seroprevalence among Hong Kong poultry workers highlight the potential for avian viruses to transmit to humans, particularly those with occupational exposure. Such transmission increases the likelihood of reassortment between a currently circulating human virus and an avian virus and thus the creation of a strain with pandemic potential. All human cases have coincided with outbreaks of highly pathogenic H5N1 avian influenza in poultry.
All evidence to date indicates that close contact with dead or sick birds is the principal source of human infection with the H5N1 virus. Especially risky behaviours identified include the slaughtering, defeathering, butchering and preparation for consumption of infected birds. In a few cases, exposure to chicken faeces when children played in an area frequented by free-ranging poultry is thought to have been the source of infection. Faeces from infected ducks may have contaminated swimming in water bodies where the carcasses of dead infected birds have been discarded or which or other birds might be another source of exposure. In some cases, investigations have been unable to identify a plausible exposure source, suggesting that some as yet unknown environmental factor, involving contamination with the virus, may be implicated in a small number of cases.
Situation in India
The first outbreak of Avian Influenza occurred in domestic poultry on 18th February 2006 in Navalpur village in Maharashtra. Over 1.5 lakh birds were killed in Maharashtra and the loss was estimated at Rs.20 crore. The strain reported was H5N1.The reported outbreaks continued through April 2006.On 25th July 2007; an outbreak occurred in backyard poultry, the first report since April 2006 in Chingmeirong village, East Imphal District of Manipur. Samples tested at the High Security Animal Disease Laboratory in Bhopal and the National Institute of Virology in Pune confirm that the samples are positive for H5N1 strain of Avian Influenza.
The Ministry of Health and Family Welfare has informed WHO that no human cases of H5N1 infection have been detected to date. Tests conducted on samples taken from persons under investigation and their close contacts have yielded no positive results as of today.
In India, as in all countries experiencing their first outbreaks of highly pathogenic H5N1 avian influenza, WHO strongly recommends that patient samples be sent to WHO collaborating laboratory for diagnostic confirmation. Certainty about the status of human cases in a newly affected country is important for accurate risk assessment.
In addition, analyses conducted by WHO approved laboratories can yield information about the possible evolution of the virus and clues about how the virus may have arrived in the country. Genetic and antigenic studies of circulating viruses also help ensure that work on the development of a pandemic vaccine strays on track.
Conclusion
Outbreaks caused by the H5N1 strain are presently of the greatest concern for human health. In assessing risks to human health, it is important to know exactly which avian virus strains are causing the outbreaks in birds. All available evidence points to an increased risk of transmission to humans when outbreaks of highly pathogenic avian H5N1 influenza are widespread in poultry. There is mounting evidence that this strain has a unique capacity to jump the species barrier and cause severe disease, with high mortality, in humans. There is no evidence, to date that efficient human to human transmission of H5N1 strain has occurred and very often. Efficient transmission among humans is a key property of pandemic strains and a property that the avian H5N1 and H9N2 viruses apparently lacked. The biological and molecular basis for effective aerosol transmission among humans is not known. The virus can improve its transmissibility among humans via two principal mechanisms. The first is a “reassortment” event, in which genetic material is exchanged between human and avian viruses during co-infection of a human or pig. Reassortment could result in a fully transmissible pandemic virus, announced by a sudden surge of cases with explosive spread.
The second mechanism is a more gradual process of adaptive mutation, whereby the capability of the virus to bind to human cells increases during subsequent infections of humans. Adaptive mutation, expressed initially as small clusters of human cases with some evidence of human-to-human transmission, would probably give the world some time to take defensive action, if detected sufficiently early.
As the number of human infections grows, the risk increases that a new virus subtype could emerge, triggering an influenza pandemic. Humans as well as swine must now be considered a potential mixing vessel for the generation of such a virus. This link between widespread infection in poultry and increased risk of human infection is being demonstrated right now in Asia.
However, urgent control of all outbreaks of avian influenza in birds - even when caused by a strain of low pathogenicity - is of utmost importance. Research has shown that certain, avian influenza virus strains, usually of low pathogenicity can rapidly mutate (within 6 to 9 months) into a highly pathogenic strain if allowed to circulate in poultry populations. Altogether, more than half of the laboratory-confirmed cases have been fatal. H5N1 avian influenza in humans is still a rare disease, but a severe one that must be closely watched and studied, particularly because of the potential of this virus to evolve in ways that could start a pandemic. The challenge for all of us is to gain an under-standing of how just 10 or 11 proteins of these viruses to replicate and be transmitted not only bet-ween hosts of one species but also between species.
References
1. Katz, J.M., (2003):Avian Diseases 47: 914-920.
2. Kawaoka, Krauss, S., and Webster, R.G., (1989):Journal of Virology 63: 4603- 4608.
3. Li, K.S., et.al.(2003): Journal of Virology77(12): 6988- 6994.
4. Murphy, F.A., Gibbs, E.P.J., Horzinek, M.C., and Studdert, M.J., Veterinary Virology, 3rd Edition, Academic Press, New York: 466- 468.
5. Taubenberger, J.K., (2003): Avian Diseases 47:789-791.
6. Toshihiro Ito, J. et.al.(1998): Jour. of Virology 72(9): 7367- 7373.
by : Mohan. M1, Trevor Francis Fernandez2 and Feroz Mohammed.M.S.3
from : http://www.veterinaryworld.org
Thursday, November 20, 2008
Avian Influenza infection in Human
Use of PVC sheet for Repair of fracture in Eagle
Introduction
The fracture of wing is not so common condition in free-range birds. This may sometime occur because of trauma or accidents as wing bones are thin and brittle with large medullary canal (Bennett and Kuzma, 1992). It is very difficult to put bandage over such bones as it increases weight of the wings that disturbs the normal posture and balance of bird. The present paper deals with the efforts to decrease weight of bandage, at the same time given full rigidity and toughness using PVC sheet as plastering material.
History and Observation
An adult male eagle was presented at Pet clinic and care centre, Akola, with the history of trauma due to unknown cause and was unable to fly. Bird was restless and trying to fly but was not able to fly. After clinical observation, the case was diagnosed as a compound fracture of humerus bone of left wing. There was swelling of area due to blood clot. The skin was opened and piece of sharp ends of fractured bone could be seen. Hence it was decided to operate the bird using some new technique other than described elsewhere (Martin and Ritchie, 1994).
Surgical Treatment:
The feathers around the fractured area were plugged out. Local anaethesia at about 3-5 ml (2% procaine HCl) was infiltrated locally around the growth (Hoque, 2001). The area was washed and cleaned with normal saline and was painted with antiseptic. The fractured ends then aligned properly and kept in opposition. After putting cotton bandage, 2mm thick PVC sheet of size 4"×1" was made pliable by putting it in the hot water for2-4 min. for allowing proper fitting over bone. These two plates were tied over using sutured nylon (by passing through skin) and a knot was applied as three pairs. Then the wing was bandaged to restrict the movement of wing . Before applying bandage, the wound was powdered with antibiotic, ampicillin. On third day, the bandage was opened and the site was dressed with antiseptic and 50 % hydrogen peroxide (H2O2) and the powder was dusted around the stitches for next 10 gays. On removal of plates on 25th day, complete healing of the area was revealed and bird was able to fly.
References
1. Bennett, R.A. and Kuzma, A.B. (1992): Joul. Zoo wildl Med 23 (1): 5-23.
2. Hoque, M., Maith, S.K. Singh G. R. Arora, B. M. and Pratap, K.(2001): Intas Polivet. 2 (11): 266-267.
3. Martin, H. D. and Ritchie B.W. (1994). Orthopedic surgical techniques. In Ritchie BW, Harrison GJ, Harrison (eds.) Avian Medicine: Principles and application. Wingers Publishing, Inc. Lake Worth, FL pp1137-1169.
by : G. P. Manjulkar1, P. R. Zade2 and V. P. Pathak3
From : http://www.veterinaryworld.org
A case report of Pigeon Pox-Histopathologic Diagnosis
Avian pox is a well-known disease in chickens, turkeys, pigeons, and canaries, and it has been identified in more than 60 wild bird species (Tripathy, 1991). Avian pox is a transmissible disease that is spread by several kinds of vectors: biting arthropods such as mosquitoes and mites, and aerosols generated from infected birds, or the ingestion of contaminated food or water. The disease has two forms: cutaneous and diphtheritic. Pigeon pox is a slowly developing disease resulting in morbidity and mortality among all age groups and sexes. The disease may be complicated with parasitism or poor condition of the flock. A case of cutaneous form of pigeon pox is presented.
Case History and Discussion
During March 2006, two local breed of pigeons were brought by local people to the dispensary with the history that they were found dead and lying along the roadside. On examination, they were found to be dehydrated and emaciated in nature. Several 0.5-1 cm diameter coalescing, round, yellowish, rough and firm masses were found at the eyelids, beak, and the mouth, and some were superficially ulcerated. Diphtheritic lesions were not found in birds. Histologic sections of skin containing the nodular lesions had cords and large clusters of markedly hypertrophic and hyperplastic epidermal stratified squamous epithelium, surrounded by dense fibroblastic stroma. Lesions consisted of swollen and pale keratinocytes with a foamy, vacuolated cytoplasm and single, round, dense eosinophilic intracytoplasmic viral inclusions (identified as Bollinger bodies). Inclusions distended the cell cytoplasm, producing cell necrosis. Some of them had clear, unstained, central rounded spaces. The superficial epidermis of the lesions was ulcerated with eosinophilic, amorphous keratinaceous crusts and necrosis.
On the basis of necropsy results, histopathologic features, and the presence of viral intracytoplasmic inclusions in epidermal cells, a diagnosis of poxvirus infection was made. In some cases, the diagnosis of a pox virus infection can be suspected by external clinical examination and gross lesions (Heuschele, 1986), but it is necessary to confirm the disease in the cutaneous form by the presence of characteristic Bollinger bodies in epithelial cells of epidermis observed in histopathologic analysis, by electron microscopy for viral particles in epidermal cells, or by virus isolation (Heuschele, 1986 and Randall and Reece, 1996). In this bird, gross lesions were compatible with an avian pox diagnosis, and this fact was confirmed by the histopathologic analysis performed on bird. An outbreak of pigeon pox involving eight local golla breed of pigeons in rural areas of Bareilly district was reported. Deaths in a few cases was recorded which might have been aided by heavy parasite load (Rajendra Singh et al., 1990).
Mortality and morbidity due to poxvirus infection may be very high in pigeons (Tripathy, 1991). Nevertheless, Pox virus is not fatal in all infected individuals, but it can reduce viability and predispose affected birds to predation, secondary infection, and accident (Reece, 1989). Thus Pox virus infection was an important, if not the direct, cause of death in bird.
by : M. Mohan and Trevor Francis Fernandez
From : http://www.veterinaryworld.org
A new Polyherbal formulation to control bacterial enteritis in poultry: a case study in Salmonella enteritidis induced experimental model
by: K.K.Baishya, Shivi Maini and K.Ravikanth
1) Veterinary Officer, Kashipur, Uttaranchal, India.
2) Scientist, Ayurvet Limited, Vill. Katha, P.O.Baddi, Dist. Solan (H.P.), India.
Abstract
An experiemental study was conducted in day old 150 VenCobb chicks to evaluate efficacy of polyherbal formulation in induced bacterial enteritis with Salmonella enteritidis.
Birds were randomly divided into three groups: negative control, infected and untreated control & prophylactically treated group with AV/ADC/16 (14th-28th days). Salmonella infection was induced on day 21st. A significant decrease in overall growth, productivity, feed conversion and mortality was evident in untreated infected group in addition to severity of clinical signs. However, prophylactic administration of herbal formulation reduced mortality and clinical symptoms were mild to negligible. No negative effect on growth & performance was observed in treated group III.
Keywords: enteritis, polyherbal, antidiarrhoeal, performance.
from : http://www.veterinaryworld.org/Vol.1%20No.11%20Abstracts
Epidemiological studies (parasitological, serological and molecular techniques) of Trypanosoma evansi infection in camels
Epidemiological studies (parasitological, serological and molecular techniques) of Trypanosoma evansi infection in camels (Camelus dromedarius) in Egypt
Ahmed Abdel-Rady
Department of Animal Medicine, Infectious diseases,
Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt
Abstract
Trypanosomosis in camel caused by Trypanosoma evansi is still a serious problem in camel husbandry causes considerable economic losses in many camel-rearing regions of the world. In the present study 193 camels clinically suspected for surra were examined parasitologically by Giemsa stained blood smear (GSBS) and haematocrit centrifugation technique, serologically for detection of anti-trypanosomal antibodies by card agglutination test for trypanosomes (CATT), and for DNA amplification, by Polymerase chain reaction (PCR), with primers yielding a 177 bp PCR product for the specific detection of Trypanozoon parasites. Out of 193, eight camels were positive by GSBS (4.1%) while 12 were positive with haematocrit centrifugation technique (6.2%). Detection of anti-trypanosomal antibodies with CATT yielded 84 positive samples (43.5%). Using PCR 110 out of 193 were positive (56.9 %). PCR technique is accurate, more sensitive and specific method for diagnosis of trypanosome infected camels than parasitological techniques; it overcomes the problem of specificity and can detect low parasitemic camels in chronic cases. The PCR proved to be the best test used for detection of camel trypanosomosis in Egypt.
Keywords: Camels, Trypanosomosis, Stained Blood smear, Haematocrit centrifugation technique (HCT), Card agglutination test (CATT), Polymerase chain reaction (PCR)
from: http://www.veterinaryworld.org
Monday, November 3, 2008
Studies on potential fowl cholera vaccine
The avian disease fowl cholera has consistently plagued the poultry industry for many years and has led to excessive monetary losses. Although better management of layer birds and use of inactivated and live vaccines have been in place, fowl cholera remains an inadequately controlled problem. In fact, the use of some of the current vaccines has resulted in fowl cholera outbreaks within the flock. Thus, the poultry industry has a need for a safe, rationally attenuated vaccine against fowl cholera. Therefore a study was initiated with the main objective, in the short-term, to further the development of a rationally attenuated live vaccine against fowl cholera using the P. multocida X-73 mutant in which the genes pnhA and pnhB have been inactivated.
Preliminary studies suggest that X-73 mutant was attenuated for virulence. The recombinant pnhA protein from P. multocida (strain X-73) was successfully isolated and purified. Biochemical and enzymatic studies of the purified pnhA confirmed that this protein was a Nudix hydrolase, more specifically, classified as a dinucleoside oligophosphate pyrophosphatase.
pnhA has properties very similar to other dinucleoside oligophosphate pyrophosphatase, and the preferred substrate target for the enzyme is diadenosine pentaphosphate.
Further studies of the complemented X-73 mutant using the chicken embryo-lethatlity assay showed an incomplete restoration of virulence. The complemented X-73 mutant contains a functional pnhA gene, but an inactivated pnhB gene. From our studies it was assumed that a functional pnhB gene was necessary to restore virulence within the mutant and that the function of pnhA in pathogenesis requires a functional pnhB protein.
Due to unforeseen problems with the stability of the X-73 mutant, bird trials and thus vaccine assessment was not performed in this study.
The pnhA protein is the first Nudix hydrolase identified within the Pasteurellaceae family. Nudix hydrolases have been shown to play a role in the pathogenesis of other bacterial pathogens. The X-73 mutant has potential as a trial vaccine, which may control fowl cholera, but further work beyond the extent of this project is needed to further develop the X-73 mutant.
Vaccine development for this disease is important because the disease has been controlled by the use of antibiotics which are costly and P. multocida has the potential to become resistant to the antibiotics in use.
Source: Carmel Ruffolo, Ph.D., Department of Biological Science, University of Wisconsin-Parkside, Kenosha, WI, USA.
Tuesday, October 7, 2008
Melamine milk crisis
Countries to ensure safe feeding for infants and increase vigilance
Geneva/Rome, 26 September 2008 – The World Health Organization (WHO) and the
UN Food and Agriculture Organization (FAO) are urging affected countries to
ensure safe feeding of millions of infants following the ongoing melamine
milk crisis in China. The two agencies also called on countries to be alert
to the possible spread of melamine contaminated dairy products.
Safe feeding
"While breastfeeding is the ideal way of providing infants with the
nutrients they need for healthy growth and development - it is also critical
to ensure that there is an adequate supply of safe powdered infant formula
to meet the needs of infants who are not breastfed," said Jørgen Schlundt,
Director of the WHO Food Safety Department.
Replacing powdered infant formula with other products such as condensed
milk, honey mixed with milk, or fresh milk is inappropriate as such products
would put at risk the safety and nutritional status of this vulnerable
population group, the two agencies advised.
"Restoring consumer confidence is critical. Melamine-contaminat ed products
should be removed from the food chain in order to prevent further exposure.
The safe supply of dairy products needs to be restored immediately,” said
Ezzeddine Boutrif, Director of the FAO Nutrition and Consumer Protection
Division.
WHO recommends that all infants should be fed exclusively with breast milk
for the first six months of life. No other liquid or food, not even water,
is needed during this period. Thereafter, infants should receive adequate
and safe complementary foods while breastfeeding continues up to two years
of age and beyond.
Increased vigilance
Countries should closely monitor their markets, following reports of
findings of imported melamine-contaminat ed products in several countries
over the last two weeks.
The two agencies highlighted that melamine-contaminat ed products could reach
markets in other countries through both formal and informal trade. Getting
information about the origin of the product, up to date recall information
or in some cases testing for melamine contamination might be considered. If
found contaminated, appropriate actions such as product recall and safe
disposal should be taken, based on an assessment of the risk to human
health.
Food safety is not the sole responsibility of public authorities. The food
industry is also responsible for ensuring a safe supply of food to the
consumer.
“It is critical that the industry strongly invests in food safety and adopts
a food safety culture covering the food chain from raw materials through to
the final product,” Boutrif said. Incidents such as this not only impact
food safety and human health but also put the livelihoods of hundreds of
millions of dairy farmers at risk. "There is a need for countries to do
major investment in strengthening their food control and food-borne disease
surveillance systems as it could minimise the potential occurrence of food
safety incidents like this one," Schlundt said.
The melamine-contaminat ed dairy products event first came to the attention
of the international organizations on 11 September. Both WHO and FAO have
used the International Food Safety Authorities Network (INFOSAN) to inform
and update national food safety authorities on this food safety crisis, one
of the largest in recent years.
Over 54,000 children have sought medical treatment in China related to the
consumption of melamine-contaminat ed infant formula. Almost 12,900 are
currently hospitalized.
Melamine is commonly used in food contact materials (e.g. containers,
labels, etc.) and can also be used in agriculture production such as
fertilizer. Whether this has a potential for carry over into food at low
concentrations (usually in the range of microgram per kilogram) and further
impact on human health may need further evaluation. Melamine alone is of low
toxicity, however animal studies have suggested that kidney problems occur
when melamine is present in combination with cyanuric acid, a potential
impurity of melamine. The level of melamine found in the contaminated infant
formula has been as high as 2,560 miligram per kilogram ready to eat
product, while the level of cyanuric acid is unknown.
From: www.fao.org
