CHOLERA

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Cholera bed

GENERAL INFORMATION

Disease

Cholera is an acute intestinal infection acquired by consuming contaminated food, milk, or water; the most common source is raw or undercooked shellfish. Person-to-person transmission is rare.

• The incubation period is usually 1-3 days but can range from a few hours to 5 days.
• In highly symptomatic cases, cholera is characterized by severe, dehydrating diarrhea with significant loss of electrolytes.
• Cholera is a major health consideration around the world in developing countries with poor sanitation.

The V. Cholera species  has 140 subgroups divided into 01 group antigen and non 01 antigen

The gram-negative bacillus that causes cholera in most areas is Vibrio cholerae 01, the El Tor strain.

A newer non-01 cholera strain, V. cholerae 0139 Bengal (commonly known as Bengal cholera), has appeared in many areas of Asia (Bangladesh, China, Hong Kong, India, Malaysia, Myanmar, Nepal, Pakistan, Singapore, Sri Lanka, and Thailand), where the 01-type strain causes illness as well. First detected in India in 1992, it has not spread beyond Asia.

Red: risk of epidemics- Purple: Recent outbreaks – Dots: 2001 oubreaks

Pink: no data

Diagnosis:

Dark-field microscopic exam of stool wet mount.

Stool cultures - Biochemical confirmation of various serotypes

Treatment:

Primary treatment is re-hydration via po( ORS)  or IV ( Normal saline + KCL)

Antibiotic: Cipro 500 BID , Doxycycline100mg BID .

Entry Requirements

WHO and CDC indicate that no country currently reports under the International Health Regulations that it requires cholera vaccination for arriving travelers. Local authorities in some developing countries may still "unofficially" require a cholera vaccination for arriving travelers.

• In most cases, these "requirements in practice" depend on a traveler's having visited an infected country prior to arrival in the country that has the requirement.
• In countries that have "requirements in practice," enforcement may be very sporadic (e.g., enforced only at certain ports of entry or by one local entry official but not another).
  • According to the Saudi Arabian Embassy in the USA, persons applying for visas for Hajj or Umra pilgrimage to Mecca are no longer  required to provide proof of cholera vaccination.

• Local authorities in some areas may administer vaccinations using contaminated needles and syringes, increasing travelers' risks of contracting hepatitis B, HIV, or other infections.
• Counsel travelers not to allow themselves to be immunized for cholera in unsanitary settings in developing countries. Supply “cholera not medically indicated stamps” or "Cholera Exemption Letter"  to travelers.

Prevention:

1. Safe food and drink precautions ( special attention to seafood)
2. Vaccine: Mutacol

• Indications: For immunization of adults and children 2 years of age and older against disease caused by V. cholerae.. Immunization should be completed at least 1 week prior to potential exposure to V. cholerae.
• Selective immunization against cholera is recommended for travelers to areas of the world with a risk of exposure to cholera and for travelers to countries requiring evidence of cholera vaccination for entry.
• Not all recipients of Mutacol Berna Vaccine will be fully protected against cholera. It however protect from a severe form leading to rapid dehydration. Travelers should take all necessary precautions to avoid contact with or ingestion of potentially contaminated sources of food or water.
• Mutacol Berna vaccine will not afford protection against enteric organisms other than V. cholerae. An optimal booster dose has not yet been established. However, it is recommended that a booster dose be taken every 6 months under conditions of repeated or continued exposure to cholera
• Contra-Indications: Hypersensitivity to any component of the vaccine or the buffer

Adverse Reactions: Reported adverse reactions include nausea, abdominal cramps and diarrhea.

• Dosage And Administration: The sachet containing the buffer (Chamber A) and vaccine (Chamber B) should be inspected to ensure that the foil is intact. The vaccine is to be swallowed approximately 1 hour before a meal.
• The vaccine is to be reconstituted in the following manner (see diagram on sachet). The sachet is to be folded along the solid black line and cut along the dotted line after ensuring that the contents have been displaced to the bottom to prevent spillage. The contents of both chambers are to be emptied simultaneously into 100 mL of cold or lukewarm water (temperature not to exceed body temperature, e.g., 37°C). Do not resuspend in milk, juice or in a carbonated beverage. Resuspend the sachet contents by gently mixing for 5 to 10 seconds. The vaccine should be swallowed as soon after mixing as possible. Not all recipients of Mutacol Berna vaccine will be fully protected against cholera.
• Booster: The optimum booster schedule for Mutacol Berna vaccine has not been determined. Efficacy has been shown to persist for at least 6 months.

Dr Assad