(Petaling Jaya, Thursday): I call on the Government to halt and review pig mass destructions operations in view of increasing queries, not only by pig farmers but also by international medical experts, as to whether pigs tested Nipah virus positive merely reflected past infections for many years.
In Paya Mengkuang, Malacca, five pig farms have been tested as Nipah virus positive and the Veterinary Services Department have ordered the 30,000 pigs in the farms to be destroyed.
However, the Veterinary Department had virtually ordered a total quarantine and restriction of movement of the some 150,000 pigs in the 102 pig farms in the area, creating an immediate crisis for the pig farms where Nipah virus tests have not been positive- as the imposition of restriction of movement of the pigs means a freeze of their sale, the immediate cessation of animal feed credit and the prospect of immediate financial ruin and collapse of the pig farms.
What is doubly tragic in Paya Menkuang is that the pig farmers in the area had taken pride in maintaining the highest standards of environmental hygiene. Furthermore, there had not been a single case of any human being falling sick from viral encephalitis or sick, dying or dead pigs since the onset of nipah virus epidemic.
The queries by the pig farmers in Paya Mengkuang about the correctness of the pig mass destruction programme in cases where Nipah virus tests have been found to be positive have been strengthened by queries by international medical experts.
For instance, this is the query just posted on the Internet medical email conference website, ProMED, which had been tracking the outbreak of the Nipah virus from a scientist from the University of Edinburgh, Scotland:
"Is anyone in Malaysia considering that Nipah virus may have been around for many years, just as Lassa Fever [occurred] in West Africa for many years before it was separated from other conditions and identified with its present name ?
"Maybe these antibodies reflect past infections which were asymptomatic or attributed to other causes.
"Are there stored sera from the past, from people or from other species, which could be tested? Positive sera from the past might suggest different reactions to present circumstances."
This has led the moderator of the ProMED to respond:
"We have no information that would answer these questions.
However, given that considerable brain power is being focussed on the Nipah
virus problem, in Malaysia, in the U.S., and in Australia, and that scientists
from all three countries are working on this problem, it is unimaginable
that no
one would have considered these questions. Serum samples
from pigs and other animals likely are in a freezer somewhere. With
all there is to do at this time, it likely has been judged that these samples
will still be available later on. First there is an epidemic to control.
"We already know that pigs were infected months before the present epizoodemic was recognized as such. Given that the presence of antibody to Nipah virus in pigs is being taken as evidence of recent/current infection in Malaysia, finding that pigs (particularly asymptomatic pigs) had antibody to Nipah virus some years ago would stir an even larger hornet's nest. If anyone knows of a collection of pig serum samples from Malaysia or from adjacent countries, please let us know and we will put you in contact with the right people to test them."
In fact, a week ago, a moderator of the ProMED electronic mail conference, Charles H. Calisher, Professor of Microbiology, Colorado State University, Fort Collins, USA expressed his exasperation when he said he was "getting tired" in "seeing all these messages about pig-killing exercises, ill-defined diagnoses, and unscientific statements attributed to uninformed politicians" about the Nipah virus outbreak, which provoked him to write the following long critique of the Malaysian government’s mishandling of the viral disaster:
"From the very outset of this Nipah virus epidemic -- whenever
that was -- we have been bombarded with misinformation and misstatements.
I have not seen or heard of a shred of evidence
that there has been a single confirmed case of Japanese encephalitis
[in peninsular Malaysia] since very early 1999, either in humans or in
pigs.
"If such data are available, we would welcome them and would post them immediately on ProMED-mail.
"The basic problem remains definitions for ‘a case’ and ‘an infection
with’. Antibody to a virus in a serum sample from an ill person or pig
(or horse or anything else) is confirmatory of nothing. Yet the Malaysian
authorities are reported to have publicly pronounced this many cases of
JE virus and that many cases of Nipah virus. A confirmed ‘positive’,
in terms of a human or a pig, depends upon either virus isolation or a
change in antibody titers between paired acute- and convalescent-phase
serum samples.
"No doubt finding IgM antibody in a single serum sample from a sick human (or pig) provides excellent presumptive data, but it does not provide confirmatory evidence of recent infection.
"We have heard nothing regarding persistence of Nipah virus in pigs.
If there is evidence that persistent infections occur, we would like to
know that -- as would everyone else. If there is no
evidence for such a persistent state, then why are pigs that are
‘positive’ (assuming this means they have been shown to have antibody in
a single serum sample) being killed? Seems to me these immune animals
would be the ones to retain.
"Until we begin to receive real data, rather than statements from government spokespeople, ProMED-mail will not post repetitive and unhelpful reports, but will continue to post messages regarding areas newly discovered to have infected animals, and other important data.
"No further mention of Japanese encephalitis will be made here unless some confirmatory evidence is presented that JE virus is still circulating or has infected even one human or one pig since, say, January 1999.
"Terms such as ‘VE’, meaning ‘virus encephalitis’, are obfuscating with regard to whether a human or a pig has Japanese encephalitis or Nipah virus.
"The Malaysian government task force responsible for investigations
of the epizoodemic of Nipah disease is still called the ‘State Japanese
encephalitis/Nipah Task Force’, which suggests that JE is not only a current
problem but THE principal curent problem. It could as well be called
the State Ebola/Yellow Fever/Nipah Task Force and be just as accurate.
Indeed, The New Straits Times Press (Malaysia) Berhad, Sat 24 Apr 1999)
quoted Health Minister Chua as having said that there were more than 13
000 malaria caseslast year but no yellow fever cases. He could have added
no
smallpox either.
"Personally, I suspect that the actual situation with regard to
the causes of this epizoodemic, the political reasons and repercussions
deriving therefrom, and the overall logistics have not begun to be mentioned.
I have received, addressed to me personally, many messages from people
in Malaysia
who have told me of scientific personnel in Malaysia being threatened
with firing, transfers, and funding reductions if they continue to speak
out in conflict with official statements, and of other even more heinous
accusations.
"The free exchange of information can never cause the expansion of an epidemic, and statements that the public should not panic cannot begin to assuage public feelings that the entire story is not being told."
Malaysia’s international standing cannot be enhanced if scientific personnel in Malaysia are "being threatened with firing, transfers, and funding reductions if they continue to speak out in conflict with official statements, and of other even more heinous accusations" and I call on the Deputy Prime Minister who is chairing the Cabinet Committee on the disastrous viral outbreak to take action to put a stop to such a culture which subordinates intellectual and scientific integrity to the political needs of the government of the day.
Unless the Cabinet is prepared to give full compensation for every pig destroyed at the rate of RM250 per pig, it should convince the pig farmers in dialogues attended by members of the Cabinet Committee on Nipah virus as well as high government officials to get their agreement and consent to the pig culling operations.
(20/5/99)