Published Date: 1999-07-15 23:50:00
Subject: PRO> Paratyphoid - India (New Delhi): increasing
Archive Number: 19990715.1187
PARATYPHOID INDIA (NEW DELHI): INCREASING
*******************************************
A ProMED-mail post
<http://www.healthnet.org/programs/promed.html>
See Also
Paratyphoid Fever, imported - Taiwan 960912113422Typhoid/paratyphoid, imported - UK 970530164747
Date: Tue 13 Jul 1999
From: ProMED-mail <promed@usa.healthnet.org>
Source: Emerging Infectious Diseases, Vol. 5, No. 3, MayJune 1999 [edited
<http://www.cdc.gov/ncidod/eid/vol5no3/letters.htm>
Paratyphoid Fever in India: An Emerging Problem
------------------------------------
An outbreak of enteric fever due to a single _S. paratyphi_ A strain in an
urban residential area was reported in 1996 from New Delhi, where
contaminated water was implicated as the probable source. This outbreak
prompted a retrospective analysis of the laboratory records of the All
India Institute of Medical Sciences, New Delhi, over a 5-year period
(1994-1998) to study the change, if any, in the etiology of enteric fever
in North India.
We evaluated all blood culture records from the institute's clinical
bacteriology laboratory for April to October (the months with the highest
number of enteric fever cases) each year. Records were from patients
residing in New Delhi and the surrounding areas of North India. The blood
was collected by a phlebotomist in the outpatient department or by a
resident doctor in hospital wards. Blood cultures were carried out by
standard laboratory technique. Bacterial identification was accomplished by
standard microbiologic protocol. Susceptibility to antibiotics
(amoxycillin, chloramphenicol, cotrimoxazole, gentamicin, ciprofloxacin,
and ceftriaxone) was tested by the comparative disk diffusion method
(Stokes method).
The total number of blood cultures performed for enteric fever cases (10
109 in 1994, 12 092 in 1995, 17 652 in 1996, 15 997 in 1997, and 17 012 in
1998) did not change significantly over this period. [I would have thought
that a fluctuation from 10 000 to well over 17 000 would be significant -
Mod.JW
The isolation of _S. typhi_ changed little (Chi-square = 2.367; p = 0.123;
statistically not significant). However, the proportion of _S. paratyphi_ A
isolates rose from 6.5% in 1994 to 44.9% in 1998 (Chi-square = 22.20; p
<0.001; statistically significant). The proportion of _S. paratyphi_ A
isolations in enteric fever cases from 1994 to 1998 was 6.5%, 21.2%, 50.5%,
30.7%, and 44.9%, respectively. Even excluding the strains from the 1996
outbreak, we found that the proportion of _S. paratyphi_ A in enteric fever
cases increased compared with _S. typhi_ (Chi-square = 30.528; p <0.001).
With our catchment area, case definition of enteric fever, and laboratory
methods remaining the same during this period, it appears that the etiology
of enteric fever in North India is changing significantly.
The age-wise distribution of _S. typhi_ and _S. paratyphi_ A showed that
_S. typhi_ was a significant isolate from children less than 5 years of
age, while this distribution was not observed for _S. paratyphi_ A, which
involved those more than 5 years of age. Sex was not significantly
associated (mean male to female sex ratio was 32.4:18 for _S. typhi_ and
15.8:10.6 for _S. paratyphi_ A).
_S. typhi_ has become increasingly sensitive [sic to amoxycillin,
chloramphenicol, and gentamicin, increasing from 75.1% in 1994 to 96.6% in
1998 for amoxycillin, from 71.9% in 1994 to 91.6% in 1998 for
chloramphenicol, and from 96.4% to 100% for gentamicin. [This would seem to
be in opposition to the general trend towards resistance - Mod.JW
_S. paratyphi_ A strains have remained uniformly sensitive (100%) to all
antibiotics (amoxycillin, chloramphenicol, and gentamicin, as well as
ciprofloxacin and ceftriaxone) used in the treatment of enteric fever. In
light of reports of multidrug resistance in _S. typhi_, especially to
quinolones [this seems to contradict the previous para. - Mod.JW,
continued surveillance and monitoring of antimicrobial sensitivity of _S.
paratyphi_ A strains are needed.
The increase in proportion of _S. paratyphi_ A cases, which may be due to a
high degree of clinical suspicion (with mild fever cases investigated for
enteric fever), changing host susceptibility, or even change in the
virulence of the organism, should be further investigated.
Seema Sood, Arti Kapil, Nihar Dash, Bimal K. Das, Vikas Goel, and Pradeep Seth
All India Institute of Medical Sciences, New Delhi, India.
References: see URL above
--
ProMED-mail
e-mail: promed@usa.healthnet.org
.................................................jw/es
--
*##########################################################*
ProMED-mail makes every effort to verify the reports that
are posted, but the accuracy and completeness of the
information, and of any statements or opinions based
thereon, are not guaranteed. The reader assumes all risks in
using information posted or archived by ProMED-mail. ISID
and its associated service providers shall not be held
responsible for errors or omissions or held liable for any
damages incurred as a result of use or reliance upon posted
or archived material.
************************************************************
Visit ProMED-mail's web site at <http://www.promedmail.org>.
Send all items for posting to: promed@promedmail.org
(NOT to an individual moderator). If you do not give your
full name and affiliation, it may not be posted. Send
commands to subscribe/unsubscribe, get archives, help,
etc. to: majordomo@promedmail.org. For assistance from a
human being send mail to: owner-promed@promedmail.org.
############################################################
############################################################