Several equine viral agents with potential for human infection have been reported in Argentina.. The following background information is abstracted from Gideon www.GideonOnline.com and the Gideon e-book series. [1,2]

1. TOGAVIRIDAE
A. Eastern equine encephalitis:
Seropositivity toward eastern equine encephalitis virus was demonstrated in wild and domestic birds, wild mammals, and horses during 1977 to 1980.
– The principal mosquito vector is Aedes (Ochlerotatus) taeniorhynchus.
– Additional vectors include Culex nigripalpus, C. caudelli, C. spissipes and C. taeniopus.
– Eastern equine encephalitis has been reported from Buenos Aires.

Notable outbreaks:
1981 – An outbreak if eastern equine encephalitis was reported among equines in Santiago del Estero Province.

B. Western equine encephalitis:
An epizootic was reported during 1982 to 1983, with continued cases to 1986.
– Ochlerotatus (Aedes) albifasciatus is the presumed vector in Argentina.
- During the epidemic of 1982 to 1983, WEE virus was also demonstrated in Anopheles albitarsis, Mansonia species and Psorophora pallescens.

C. Venezuelan equine encephalitis
Complement-fixing antibodies toward Venezuelan equine encephalitis virus have been demonstrated among humans in Corrientes and Chaco (1983 publication)
– Related agents, Pixuna and Rio Negro viruses, have been identified among rodents in Tucuman Province.

Seroprevalence surveys:
51.6% of persons on General Belgrano Island, Formosa Province (NT, 1993 publication)
30% to 70% of persons on General Belgrano Island, Formosa Province (NT, 2003 publication)

2. RHABDOVIRIDAE
A. Calchaqui virus:
Seropositivity of humans and horses toward Calchaqui virus has been demonstrated in Santa Fe Province. Calchaqui virus has also been identified in a local mosquito.

B. Rabies (an extensive note regarding rabies in Argentina is available on request)

C. Vesicular stomatitis virus infection has been reported among animals in Argentina (2011 publication)

3. BUNYAVIRIDAE
A. Cache Valley, Kairi and Bunyamwera viruses:
Seroprevalence surveys:
5.7% of human sera in Cordoba are seropositive toward Cache Valley virus and 5.92% toward Kairi virus (2004 to 2005)
13.3% of horses in Santa Fe and Cordoba are seropositive toward Kairi virus , and 40% toward Cache Valley virus (1983 to 1984)
6.6% of free-ranging birds in Cordoba City were seropositive toward Bunyamwera virus in 2004, 13.8% in 2005

4. FLAVIRIDAE
A. West Nile fever virus:
West Nile fever virus was detected for the first time in Argentina in 2006 – two horses in San Antonio de Areco and one in San Isidro, Buenos Aires Province.
– Infection was documented in free-ranging birds during 2005 to 2006.
– The country’s first cases of human infection were reported in 2006 – one case in the city of Marcos Juarez in Cordoba Province and 3 additional cases in Chaco province.

References:
1. Berger SA. Infectious Diseases of Argentina, 2011. 417 pp, 96 graphs, 1516 references. Gideon e-books, http://www.gideononline.com/ebooks/country/infectious-diseases-of-argentina/
2. Berger SA. Equine encephalitis: Global Status, 2011. 38 pp, 17 graphs, 282 references. Gideon e-books, http://www.gideononline.com/ebooks/disease/equine-encephalitis-global-status/

Following up on the post announcing the new GIDEON diagnosis module, there is now a video demonstration by Dr. Steve Berger:

Wishing you all a happy 2010!

GIDEON’s redesigned Infectious Diseases Diagnosis module has been launched (screenshot). There are many new features, including

• Suggestions
• Dynamic diagnosis
• Usability improvements

Suggestions
Until now, GIDEON’s Diagnosis Compare function has ranked signs and symptoms which are most likely to impact the Differential Diagnosis list. Now, the top four clinical findings which are most likely to focus and shorten the list of possible diseases are displayed and dynamically updated as each new sign or symptom is entered. Clickable boxes which allow the user to enter a “yes”, “no” or “unknown”, appear and enlarge each time the mouse passes near a perspective finding.

Dynamic diagnosis

The Diagnose button has been eliminated! Now, the differential diagnosis list updates automatically as you enter signs and symptoms. This feature demonstrates the effects of each new sign or symptom as it is entered.
The First case scenario list still appears below the diagnosis list.
The familiar buttons: Compare, Why Not, Open case, Save case, Remove All, Print, Email are all in the Diagnosis Results area.

Usability improvements

Country and incubation period in symptom list
Country name and Incubation period have been appended to the Clinical Presentation list.  Now, whenever you indicate a country name, or dates of exposure, the Differential diagnosis list instantly re-adjusts accordingly.

Collapsible windows
Windows, such as Suggestions and Clinical Summary can be minimized and hidden. For example to not see suggestions, click on the minimize button to the left title.

Mouse overs
More mouse-overs have been added: Clickable boxes expand as you mouse over them, and display clear symbols to select “yes” or “no.”

Clinical Summary
You can now click on the signs and symptoms in the Clinical Summary. Clicking on Country will display “Worldwide”. Clicking again displays the country.

Quick sorting
Diagnosis results can be sorted alphabetically or by probability easily by clicking the column title.

Resize window
Changing vertical window size expands size of Clinical presentation and Diagnosis results sub-windows. This is a great feature for larger monitors.

Previous version
Click “Original diagnosis” to use the older interface.

In an undiagnosed case of hemorrhagic disease in China, Marjorie Pollack, a ProMED editor, used GIDEON to help figure out the differential diagnosis. From the ProMED note:

Using the database of the Global Infectious Disease and Epidemiology Network (GIDEON ) to see possible etiologies for a hemorrhagic fever syndrome in China, the most likely diagnosis would be Old World hantavirus infection (57 percent probability), followed by _Streptococcus suis_ infection (40 percent), leptospirosis (1.8 percent) and Crimean-Congo hemorrhagic fever (CCHF — less than one percent probability).

(more…)

In 2005 an agricultural expert from Israel went for 6 days to India to participate in a farming project. He returned to Israel, and the following morning developed fever, headache, vomiting and muscle pain. Read the latest case of the month, Agriculture Expert in India, about how GIDEON helped save this person’s life.

Diagnosing a patient has just become easier with our latest feature, symptom images. As you mouse over any of the symptoms in the Diagnosis module, the signs and symptom description will display a representative photo or image. This will provide an additional visual differentiation of similar symptoms, further enhancing GIDEON diagnosis. See the example of the description of Jaundice to the left.

As a result of feedback from our users, we’ve added ICD9 and ICD10 codes to Diagnosis symptoms and the Epidemiology diseases.

In the Diagnosis module, the mouse-over description for symptoms will display the code, if available. For example, to the left is the description for “Jaundice”.

The General tab of diseases in Epidemiology will display the ICD9 and ICD10 codes below the list of disease synonyms. Synonyms and codes for Babesiosis:

The codes have been integrated both into diagnosis and text search. So if you want to diagnose an infectious disease based on the ICD9 and/or ICD10 codes for symptoms, just enter them in diagnosis search and click the button.

Likewise if you’re searching for a disease based on the ICD9 or ICD10 code, enter the code in text search and click.

Ever since we launched the web version of GIDEON, our CD customers have requested that in Diagnosis and Microbiology Identify, marking symptoms and tests should enable the right click to select “no”.
Well finally this now works. Left click will rotate from Yes to No to blank. Right click will rotate in reverse from No to Yes to blank.

ProMED provided another great example of how GIDEON can be used to diagnose an illness in Cote d’Ivoire:

When one checks GIDEON (Global Infectious Disease and Epidemiology Network) for the clinical picture associated with contact with animals, one gets 3 main possibilities — Q fever, ornithosis, and bunyaviridae. Of the bunyaviridae family, one does think of Rift Valley fever (RVF) as consistent with this clinical picture, but the involvement of poultry rules this out, as the RVF virus does not affect avians. Gideon also gives a “1st case scenario”, where it “ignores” the geographic location of the outbreak in the event that this is a new geographic extension of an otherwise known pathogen. In this case, the GIDEON program suggested Congo-Crimean hemorrhagic fever (CCHF).

We just launched a great new feature, Diagnosis search. This provides for an alternate method for entering signs, symptoms and country of acquisition. You can just type them, or their synonyms. See the Getting an Itch on Bali case of the month, or watch the video.