Posts Tagged ‘arenavirus’

Down, Lujo!

4 June, 2009

I am indebted to Ms Ngimezi Phiri – muli bwanji! – in the MCB2016F class, to whom I have just lectured Virology, for pointing this out – from Yahoo! News:

Scientists identify new lethal virus in Africa

By MIKE STOBBE, AP Medical Writer  Thu May 28, 9:15 pm ET

ATLANTA – Scientists have identified a lethal new virus in Africa that causes bleeding like the dreaded Ebola virus. The so-called “Lujo” virus infected five people in Zambia and South Africa last fall. Four of them died, but a fifth survived, perhaps helped by a medicine recommended by the scientists.

It’s not clear how the first person became infected, but the bug comes from a family of viruses found in rodents, said Dr. Ian Lipkin, a Columbia University epidemiologist involved in the discovery.

“This one is really, really aggressive” he said of the virus.

A paper on the virus by Lipkin and his collaborators was published online Thursday on in PLoS Pathogens.”

Of course, regular readers of this blog will be familiar with the Zambian arenavirus discovered under tragic circumstances last October, and covered here as follows:

Now the agent has a name – albeit an unfortunate victim of political compromise; they are calling it “Lujo” after Lusaka (where it came from, sort of) and Johannesburg, where nearly everyone who got it was treated.

The (relatively) rapid characterisation of the virus owes a lot to modern technology: in the words of the authors (MCB3019F take note – this is serious viromics…):

“RNA extracts from two post-mortem liver biopsies (cases 2 and 3) and one serum sample (case 2) were independently submitted for unbiased high-throughput pyrosequencing. The libraries yielded between 87,500 and 106,500 sequence reads. Alignment of unique singleton and assembled contiguous sequences to the GenBank database … using the Basic Local Alignment Search Tool (blastn and blastx; …) indicated coverage of approximately 5.6 kilobases (kb) of sequence distributed along arenavirus genome scaffolds: 2 kb of S segment sequence in two fragments, and 3.6 kb of L segment sequence in 7 fragments (Figure 2) [see here for depiction of arenavirus genome]. The majority of arenavirus sequences were obtained from serum rather than tissue, potentially reflecting lower levels of competing cellular RNA in random amplification reactions.”

Sequence data was used to allow primer synthesis for cDNA PCR to fill in gaps, and the whole genome is now available.  It is a novel arenavirus, with all genome segments giving the same sort of phylogenetic tree topology, which shows the virus to be near the root of Old World arenaviruses.

The authors conclude:

“To our knowledge is LUJV the first hemorrhagic fever-associated arenavirus from Africa identified in the past 3 decades. It is also the first such virus originating south of the equator (Figure 1). The International Committee on the Taxonomy of Viruses (ICTV) defines species within the Arenavirus genus based on association with a specific host, geographic distribution, potential to cause human disease, antigenic cross reactivity, and protein sequence similarity to other species. By these criteria, given the novelty of its presence in southern Africa, capacity to cause hemorrhagic fever, and its genetic distinction, LUJV appears to be a new species.”

Ex Africa, semper aliquid novi(rus)…B-)

Deadly Export

4 December, 2008

Hot on the heels of the arenavirus outbreak in South Africa recently – traced back to Zambia - comes the story of an unfortunate South African business traveller who took sick and then died in Brazil recently.  While it has been in the papers, as always, ProMED does it best:

 

Date: Wed, 3 Dec 2008 13:34:00 -0500 (EST)

From: ProMED-mail <promed@promed.isid.harvard.edu>

Subject: PRO/AH/EDR> Viral hemorrhagic fever – Brazil (02): (RJ) ex South Africa

 

VIRAL HEMORRHAGIC FEVER – BRAZIL (02): (RIO DE JANEIRO) ex SOUTH AFRICA

***********************************************************************

A ProMED-mail post

<http://www.promedmail.org>

ProMED-mail is a program of the

International Society for Infectious Diseases <http://www.isid.org>

 

Date: Tue 2 Dec 2008

Source: Ministry of Health, Brazil (in Portuguese trans. & summ.

Mod.MPP, edited]

<http://189.28.128.100/portal/aplicacoes/noticias/noticias_detalhe.cfm?co_seq_noticia=56538>

 

 

[The following additional information has been added to the Brazilian Ministry of Health statement included in the preceding ProMED-mail

post: Viral hemorrhagic fever - Brazil (RIO) ex South Africa: RFI, archive number 20081202.3792]

 

1. A 53-year-old man arrived in Brazil on 23 Nov [2008]. On 25 Nov [2008] he presented the 1st symptoms of a febrile hemorrhagic disease as yet undiagnosed.

 

2. On [28 Nov 2008], he went to 2 private hospitals in Rio de Janeiro, with a clinical picture of fever, chills, vomiting, hematuria, hepatomegaly, and small skin eruptions [?petechiae]. On [2 Dec 2008], the patient died.

 

5. One of the viruses suspected to be the cause of death of the patient is an [South African] arenavirus. It can be transmitted by direct contact with secretions or blood from rodents or from infected patients.

 

- –

Communicated by:

Naomi Bryant

Senior Information Analyst

National Travel Health Network and Centre (NaTHNaC) United Kingdom <http://www.nathnac.org/>

 

[Previously it was stated that there had been no reports of similar symptoms among health professionals who had contact with the patient, and that implementation of quarantine was not considered necessary.

Diagnoses of dengue, malaria, and ebola [hemorrhagic fever] had already been discarded. Other etiologies, such as leptospirosis, hepatitis, and hantaviruses will be investigated.

 

This additional new information suggests that the South African visitor had contracted his illness prior to arrival in Brazil, and not during travel within the country. The patient’s illness had been diagnosed as a viral hemorrhagic fever and the results of laboratory tests are awaited. There is as yet no direct evidence that the patient had contracted the novel arenavirus recently identified as the cause of an outbreak of disease associated with the treatment of a Zambian patient in South Africa. – Mod.CP]

 

Now it is a matter of fact that there are plenty of nasty arenaviruses and other haemorhhagic fever agents in South America: however, getting sick only two days after arrival would tend to point to an external (and probably South African) source for the infection.

 

Which, if it is an arenavirus, is rather worrying – given that we have seen such a thing only recently, and only in a very limited context.

 

I am sure the folk at the National Institute for Communicable Diseases (NICD) in Johannesburg, and especially the Special Pathogens Unit, who do surveillance for these sorts of nasties, are going to be busy – let us wish them luck.

———————————————————————————————————————

 And latest news (9/12/08): The Mail & Guardian web site carries this story as of 8th December.

SA man in Brazil did not die from arenavirus, says NICD

JOHANNESBURG, SOUTH AFRICA Dec 08 2008 14:35

The death of a South African man in Brazil was not caused by the arenavirus, the National Institute for Communicable Diseases (NICD) said on Monday.

The institute’s deputy director, Dr Lucille Blumberg, said laboratory tests had tested negative for the virus.


Tick-bite fever, acquired in South Africa, is the likely cause of the illness, as indicated by tests performed by the reference laboratory in Brazil.”

The fever, she said, was a well-documented cause of severe illness. It did not pose any risks to those who had been in close contact with infected people. — Sapa

And can be cured with antibiotics, seeing as it is caused by a rickettsial-type prokaryote.

Zambia Fever Revisited

24 October, 2008

Apologies for not updating more often; little things like HIV Vaccine conferences get in the way…B-)  More on that later – for now, news:

From SAPA / News24.com today:

Virus: Nurse responds to meds
24/10/2008 14:31  – (SA)

Johannesburg – The nursing sister fighting an arenavirus is showing signs of responding to her treatment, although she is still in a serious condition, the Morningside Medi-Clinic said on Friday.

Meanwhile, the number of people being monitored after coming into contact with patients who had developed the viral haemorrhagic fever associated with the virus, has dropped from 94 to 31, spokesperson Melinda Pelser said.

Three people are known to have died from the virus.

Paramedic Hannes Els became ill after accompanying Cecilia van Deventer from Zambia to South Africa in September when it was thought she had tick bite fever, and clinic nurse Gladys Mthembu died before the virus, which is associated with rodents, could be identified.

“Antiviral treatment continues and there are indications that she is responding to this treatment,” said Pelser of the nursing sister currently being treated.

Monitoring of the remaining 31 people is done while they are at home and at work and so far nobody has presented with the virus.

And from close to two weeks ago:

Mystery virus identified
12/10/2008 16:39  – (SA)

Johannesburg – The mystery viral haemorrhagic fever which killed three people in South Africa has been provisionally identified as an arenavirus, the National Institute for Communicable diseases and the Department of Health said on Sunday.

“The causative agent of the disease… may be a rodent-borne arenavirus related to the lassa fever virus of West Africa,” said NICD’s Dr Lucille Blumberg.

She said tests done by the NICD and the Centres for Disease Control in Atlanta, US indicated that the disease seemed to be a kind of arenavirus.

Arenaviruses cause chronic infections in multimammatic mice – a kind of wild mouse – who excrete the virus in their urine which can then contaminate human food or house dust.

More tests needed

Viruses similar to the lassa fever virus have been found in rodents in Africa, but other than in West Africa, have not been found to cause diseases in humans.

Therefore further tests still need to be done to find out whether this current strain is an undiscovered member of the arenavirus and what its distribution is.

Arenaviruses are enveloped ss(-)RNA viruses with 2-component genomes.  The ones affecting humans are generally rodent-associated, and are transmitted to humans by contact with rodent urine and/or faeces.  Perhaps the best known example from Africa is Lassa fever, which is found in West Africa.

Lassa fever virions

Lassa fever virions: from Wikipedia

From the Centers for Disease Control and Prevention:

What are the Arenaviridae?

From the WHO:

New virus from Arenaviridae family in South Africa and Zambia – Update
13 October 2008 — The results of tests conducted at the Special Pathogens Unit, National Institute for Communicable Diseases (NICD) of the National Health Laboratory Service in Johannesburg, and at the Special Pathogens and Infectious Disease Pathology branches of the Centers for Disease Control in Atlanta, USA, provide preliminary evidence that the causative agent of the disease which has resulted in the recent deaths of 3 people from Zambia and South Africa, is a virus from the Arenaviridae family.

So we have what looks like a new arenavirus, popping up out of Zambia most unexpectedly.  People who knew the index case – Cecilia van Deventer – are most concerned, as they know of no risks that they are not also associated with.

Watch this space….


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