61 SouthEast Asian Infectious Diseases

James Whitehorn 04/10/18

3.8 billion live in asia, with a high population density.

This is why it’s so good for new pathogens/new strains/drug resistance.

61.1 Meliodosis

Burkholderia pseudomalleia - Gram Negative Rods With BiPolar Staining

First seen in Burma in 1910.

Found in soil and surface water. Highly seasonal transmission, related to what people are doing in the soil.

SE Asia is the epicentre of the disease, but also seen in N. Australia and africa.

Majority get inoculation in skin. But also inhalation, and near drowning.

It’s also a real danger within laboratory. But doesn’t get human-human spread.

61.1.1 RF’s

  • Malignancy
  • Diabetes
  • Chronic Renal Disease/Lung Disease

61.1.2 CF’s

  • Supparative skin disease
  • Bacteraemia - widespread visceral organ abscesses
  • Pneumonia most common severe manifestation (in some parts of Thailand it’s the most common CAP)

61.1.3 Bug

Intrinsically resistant to Gentamicin.

Can look a lot like pseudomonas.

Is a Hazard Group 3 Pathogen. Real risk of transmission

61.1.4 Tests

None beyond culture yet

61.1.5 Treatment

  • V long course of ABx. Initially 2 weeks of iv abx. Resistant to most generations of.
  • Need 2 weeks acute parenteral (Ceftazidime)
  • Need 12-20 weeks eradication later
  • 1/4 patients end up in ICU
  • If abscesses need drained

61.2 Japenese Encephalitis

Another flavivirus

Spread by Culex (breed in paddies/ricepools)

Was the leading cause of viral neurological disease in Asia

3 billion live in endemic areas. ~50,000 cases reported yearly w/ ~10,000 deaths.

61.2.1 CF’s

Children

Fever and Confusion are the Main Presenting Features

30% of encephalitis patients die.

Half of survivors have residual neuro weakness

Non Specific:

  • Fever
  • Myalgia
  • Malaise
  • Headache

More Specific:

  • Photophobic/Vomiting
  • Seizures
  • Cranial Nerve Palsies
  • Hemiparesis
  • Fall in GCS

61.2.2 Tests

  • Serology - IgM - CSF/Blood

The most specific would be IgM in CSF

Down WCC, down platelets Down na (SIADH)

MRI - thalamic lesions +/- blood

61.2.3 Treat

No specific treatments

Treat raised intracranial pressure

Interferon? Steroids? No benefit

61.2.4 Vaccine

V effective, for those living in endemic areas.

Would not routinely offer vaccine for standard travellers.

But for those in rural areas, or those moving to, would offer.

61.3 Scrub Typhus

Intracellular coccobacillus. Pretty distinct from other typhus.

1 million cases in South East Asia/year

Mostly in South East Asia, but also in Americas

61.3.1 Clinical Features

  • Eschar - most helpful sign
  • Penumonitis
  • Meningoencephalitis
  • Fever
  • Headache
  • Rash
  • Febrile Illness
  • Chest Signs

Big cause of non malarial febrile illnesses

61.3.2 Investigations

Serology

61.3.3 Treatment

Empirical Doxycycline, do not wait for results of confirmatory test

61.4 Talaromyces/Penicilliosis

Dimorphic fungus endemic to SE Asia, approx 300 cases/year in Thailand

It’s a Common HIV opportunistic infection. (1 TB/2 Cryptococcus/3 Talarmyces)

Advanced disease has bone marrow involvement and funagemia. Plus skin lesions, lung infiltrates

61.4.1 Clinical Features

  • Fever
  • Malaise
  • Skin Rash
  • Weight Loss/Appetite Loss
  • Lymphadenopathy
  • Hepatosplenomegaly
  • Anaemia
  • Low WCC
  • Low Platelets

61.4.2 Treat

Amphoterecin B

For 2 weeks

Then 10 weeks of itraconozole

Then prophylactic itraconozole until CD4 > 100 for 6 months

Risk of IRIS, so 2 weeks treatment before starting ARVs