Cholera Pandemic: Seventh Wave

2. The seventh pandemic of cholera differed from the prior six. Thispandemic was caused by the biotype El Tor of V. cholerae O1, a biotypethat had been isolated for the first time in Egypt at the beginning ofthe century and was associated with sporadic cases until 1961. In 1961,the pandemic originated in Indonesia, instead ofthe Indiansubcontinent, was then spread out as follows.

5. Nature

7. Specific adherence of V. cholerae to the intestinal mucosa is probably mediated by long filamentous fimbriae that form bundles at the poles of the cells. The powerful enterotoxinthen released is a protein consisting of an active (A) subunitand five binding (B) subunits.

9. This results in an increased level of intracellular cAMP leading toan increase in intestinal chloride secretion and a decrease in sodiumchloride absorption. The outcome is a passive watery excretion thatleads to diarrhea. The volume typically exceeds 1 liter per hour inadults and 10 ml/kg per hour in children. The result of these events is the production ofwatery diarrhea with electrolyte concentrations similar to those ofplasma, as shown in Table:

10. Patients look anxious and restless, the eyes are very sunken, mucous membranes are dry, theskin has lost its elasticity and when pinched skin retracts very slowly, thevoice is almost non audible, and the intestinal sounds are prominent. A Peruvian patient with severe cholera. Sunken eyesand washer woman’s hands are typical of patients with severedehydration.