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Archive for the ‘General’ Category

Pythiosis in Humans

The following background data are abstracted from Gideon Primary references are available on request.

Human pythiosis was first described in Thailand, in 1987; and thirty-two cases had been published worldwide as of 2002.  Most cases are reported from tropical and subtropical regions; however, human infection has also been encountered in United States, Israel and Australia.  The principal pathogen is identified as Pythium insidiosum, and at least one case of Pythium aphanidermatum infection has been reported.

Most case reports of pythiosis are published from Thailand, which accounted for 78% of published reports to 2002 – over 90% of these in farmers. Pythium insidiosum is identified in irrigation water in endemic agricultural areas; and 64% of soil samples in endemic areas contain the organism. 102 cases of human infection were identified in Thailand through active case finding during 1985 to 2003 – 59% vascular, 33% ocular, 5% cutaneous / subcutaneous and 3% disseminated.

Natural infection of dogs, cats, cattle, horses, and other mammals is described in South America (Argentina, Brazil, Colombia and Venezuela), Central America and the Caribbean (Costa Rica, Guatemala, Haiti, Jamaica, Panama, and Nicaragua), North America (the United States, notably in Florida, Louisiana, Mississippi, and Texas), Australia and Asia (India, Indonesia, Japan, New Guinea, New Zealand, North Korea, and Thailand).  A single case (dog in Mali) had been reported in Africa as of 2005.

Infection is acquired through direct contact or trauma, and presents as granulomatous cutaneous and subcutaneous lesions. Patients often have underlying thalassemia. Vascular pythiosis is characterized by ascending purulent infection and thrombosis of major arteries, usually of the lower extremities. If a major vessel is involved, the patient usually dies within weeks. Symptoms include intermittent claudication, resting calf pain and other signs of arterial insufficiency. Fever and weight loss are not described.

Ocular disease is characterizewd by ulcerative keratitis which may progress to endophthalmitis and require enucleation. Eleven cases of Pythium endophthalmitis were reported from a single Thai hospital in 2004.  Legenidium, a related genus of oomycetes, has been associated with infections of the skin and eyes in Thailand.

Pythium insidiosum is not susceptible to antifungal agents, and excision is the only proven form of therapy. Saturated solutions of potassium iodide have been recommended for localized skin infections. Immune therapy consisting of injection of Pythium antigen into infected patients has been successful in animal models, and has been used for human disease in Thailand.

A single outbreak (4 cases of keratitis) of pythiosis has been reported, in Thailand in 2009; and at least three instances of cross-border pythiosis have been published:

2005 (publication year) – Pythiosis was documented in a German Shepherd dog exported from Mali to France.
2011 (publication year) – An American soldier acquired traumatic wound infection by Pythium aphanidermatum in Afghanistan.
2015 (publication year) – A French traveler acquired Pythium insidiosum keratitis in Thailand.

Ebola Deaths in Perspective

Recent events in West Africa have largely eclipsed several other ongoing outbreaks on the global stage. For example, over 780,000 cases of Chikungunya have been reported in the western hemisphere in recent months, including 1,371 cases in the United States (vs. only 4 of Ebola). Obviously, the severity of Ebola far outweighs that of Chikungunya; thus, the ratio of reported Chikungunya cases to Ebola cases (772,069 / 10,141) is 76-to-1, the ratio of Ebola deaths to Chikungunya deaths (4,922 / 118) is 73-to-1.

Sadly, one ongoing epidemic which is more severe than Ebola in both disease numbers and mortality, receives little notice from the lay media. The last available publication on cholera in Haiti reported 780,541 cases (8,562 fatal) as compared to 10,041 (4,922 fatal) of Ebola. As of October 28, cases of both diseases had been reported in nine additional countries.

The following graph illustrates mortality figures for some ongoing Infectious Disease outbreaks (I’ve added SARS for historic impact). The lower row records the number of countries which reported cases originating in the outbreak epicenter.

Outbreak Deaths

Campylobacteriosis in Iceland

A recent posting in ProMED belies the fact that Iceland reports the lowest rates of campylobacteriosis in that region of Europe. [1-2] See graph [3] Note that an earlier outbreak (436 cases) was reported in 1999.


1. Berger SA. Infectious Diseases of Iceland, 2014 371 pages, 75 graphs, 1,455 references. Gideon e-books,
2. Berger SA. Campylobacteriosis: Global Status, 2014 104 pages, 96 graphs, 1,073 references. Gideon e-books,
3. Gideon graph tool at

GIDEON and Global Disease

We have developed an on-line system which follows the status of all Infectious Diseases – in every country – in real time. One of the GIDEON modules contains an ongoing chronology of every outbreak / survey on a global / country-specific level. As of 2014, the site contains 32,000 incidence graphs + details regarding 33,000 individual outbreaks and 36,000 prevalence surveys. Sample graphs and maps follow (red dots are links to country-specific text notes in the program).

The computer server has also been engineered to publish a series of 213 eBooks (115,000 pages, 410,000 references) – with all titles updated yearly. These include the only published books on diseases of YOUR country and YOUR particular disease-of-interest – including all Neglected Tropical Disease. Full list of titles at Users can also create custom graphs which contast multiple diseases of interest – a few maps / graphs follow:






Fatal Plague in Madagascar

Madagascar accounts for most plague deaths in the world – see graph

plague deaths

Barmah Forest Disease in Australia

The following background on Barmah Forest Disease in Australia is abstracted from Gideon and the Gideon e-book series. [1,2]

Barmah Forest disease virus was first isolated from mosquitoes (Culex annulirostris) in the Barmah Forest, Northern Victoria in 1974. Human infection was subsequently reported along the south coast of New South Wales during the mid-1980’s; in Queensland during 1988 to 1989; in the Northern Territory in 1992 ; and in southwestern Western Australia in 1993. A new focus was described in Gippsland (Victoria) during 1993 to 1994. The number of localities reporting Barmah Forest Disease increased during 1996 to 1998, and again during 1999 to 2001.

Disease incidence has increased somewhat since 2000, with most cases reported from Queensland and New South Wales. In the following chart, I have contrasted incidence data for Barmah Forest disease with those of a similar illness, Ross River disease [3]


Seroprevalence surveys:
6.5% of healthy adults in Queensland.
11.3% of horses in Brisbane, 1.2% of dogs, 10.7% of bushtail possum (Trichosaurus volpecula) , 1.5% of cats, 0% of flying foxes (1977 to 1999) 8

– The known vectors are Ochlerotatus vigilax, Culex annulirostris, Ae. (Oc.) camptorhynchus, Ae. normanensis and Coquillettidia species.
– Aedes notoscriptus is considered an additional potential vector.
– BFD virus has also been recovered from Aedes vigilax in eastern Australia (2005 to 2008)

Wallabies and kangaroos serve as reservoirs for the virus; however, antibody is also present in cattle and horses.

Related viruses:
– Similar local illnesses have been ascribed to Trubanaman and Gan Gan viruses (Bunyaviridae); and Kokobera, Stratford and Edge Hill viruses (Flaviviridae).
– A single human case of Edge Hill virus infection has been described.
– A case of Kokobera fever was reported from Darwin in 1998.
– Kokobera virus has been isolated from Culex annulirostris in the Northern Territory and northern Queensland.
– Kokobera virus was isolated from 18 of 25,351 Cx. annulirostris tested in Cape York in 1998.

Notable outbreaks:
1992 to 1994 – An outbreak (22 cases) of Barmah Forest disease was reported in the south-west of Western Australia.
1995 – An outbreak (135 cases) was reported along the south coast of New South Wales.
2002 – An outbreak (47 cases) was reported in Victoria.
2002 to 2003 – An outbreak (297 cases) was reported in Queensland.
2005 to 2006 – An outbreak (1,895 cases) was reported.

1. Berger SA. Infectious Diseases of Australia, 2013. 540 pages, 162 graphs, 3364 references.
2. Berger SA. Australo-Pacific Arboviruses: Global Status, 2013. 32 pages, 20 graphs, 307 references.
3. Gideon Graph Tool, see tutorial at

Note featured on ProMed

Vaccination Uptake in Afghanistan

Although childhood vaccination has registered considerable success during the past three decades, Afghanistan continues to lag behind other nations in the region. In the following charts I have contrasted WHO estimates of vaccine uptake in Afghanstan with those of bordering countries. [1-3]


1. Berger SA. Infectious Diseases of Afghanistan, 2012. 326 pages, 37 graphs, 1239 references. Gideon e-books,
3. Gideon Graph Tool, see tutorial at

Note featured on ProMED

Pathogens Associated with Animal Bites

Gideon lists 31 species of bacteria which have been associated with human infection following the bites of animals:
– Bacteroides tectus
– Bergeyella zoohelcum
– Bisgaard’s taxon
– Capnocytophaga canimorsus
– Corynebacterium canis
– Capnocytophaga cynodegmi
– Corynebacterium freiburgense
– Corynebacterium kutscheri
– CDC NO-1
– Erysipelothrix rhusiopathiae
– Fusobacterium canifelinum
– Halomonas venusta
– Kingella potus
– Moraxella canis
– Mycobacterium vulneris
– Neisseria animaloris
– Neisseria canis
– Neisseria weaveri
– Neisseria zoodegmatis
– Pasteurella caballi
– Pasteurella canis
– Pasteurella dagmatis
– Pasteurella multocida
– Pasteurella stomatis
– Psychrobacter immobilis
– Spirillum minus
– Staphylococcus intermedius
– Streptobacillus moniliformis
– Vibrio charchariae
– Vibrio harveyi

Although virtually all literature on the subject advocates administration of tetanus prophylaxis following animal bites, few if any cases of bite-associated tetanus have been documented.

Leprosy in the Western Pacific Region

Leprosy data for the Western Pacific Region indicate that disease incidence is highest in the Philippines, Vietnam and China. In the following graph, I have contrasted incidence and prevalence statistics for countries mentioned in the ProMED note, with population-adjusted rates for these same data. [1,2] Note that the numbers of cases per 100,000 population are highest in Micronesia, Kiribati and the Marshall Islands. See graph:

1. Berger SA. Leprosy: Global Status, 2012. 236 pp, 376 graphs, 226 references. Gideon e-books,
2. Gideon graph tool at

Note featured on ProMED

Scrub Typhus in India

The following background information on Scrub typhus in India is abstracted from Gideon and the Gideon e-book series. [1]

Rickettsia tsutsugamushi is one of seven Rickettsia and Rickettsia-like organisms which have been associated with human infection in India (the others are Rickettsia sibirica, Rickettsia conorii subsp. indica, Candidatus Rickettsia kellyi, Rickettsia typhi, Rickettsia prowazekii and Coxiella burnetii)

Epidemics of scrub typhus were previously reported among troops stationed in the north and east.

Risk factors include living close to bushes and wood piles, work on farms, observation of rodents at home and at work, and raising domestic animals (Darjeeling, West Bengal, 2009 publication)

Exported cases:
– Three cases of imported scrub typhus were reported in the United States during 1983 to 1988 – all originating in India.
– In 2002, a Belgian traveler developed scrub typhus following a trip to India.

17 fatal cases were reported in Himachal during 2001 to 2002.
– 21 cases (3 fatal) were reported in Himchal Pradesh during 2004.
– Nine cases were confirmed in Uttarakhand (2010 publication)
– 29 cases were reported from a hospital in Manipal, Karnataka during 2009.

Prevalence surveys:
24.1% of febrile hospitalized patients in Vellore (2006 publication)
15% of children below age 14 hospitalized for fever in Tamil Nadu (2003 to 2004)
14.3% of children hospitalized with fever and at least one suggestive feature of rickettsial infection (central India, 2011 publication)
37.5% of febrile malaria-negative patients in Tamil Nadu in 2004, and 9.2% in 2005
47.5% of patients hospitalized for acute undifferentiated febrile illness in Vellore, Tamil Nadu (2010 publication)

The principal vector is Leptotrombidium deliense.
– Schoengastiella ligula mites infesting shrews (Suncus murinus) were identified as vectors during an outbreak in Kurseong, Darjeeling.

Notable outbreaks:
2001 to 2002 – An outbreak (28 cases, 3 fatal) was reported in Tamil Nadu.
2003 – An outbreak (225 cases, 19 fatal) was reported in Himachal Pradesh.
2006 to 2008 – An outbreak (50 cases) was reported in Pondicherry.
2007 – An outbreak (38 cases) was reported in Bishnupur district, Manipur.
2009 to 2010 – An outbreak (80 cases, 5 fatal) was reported in Meghalaya.
2011 – Outbreaks were reported in Himachal Pradesh (200 cases, 13 fatal) and Nagaland (9 cases, 3 fatal).

1. Berger SA. Infectious Diseases of India, 2011. 480 pp, 65 graphs, 3503 references. Gideon e-books,

Reproduced on ProMED