Published Date: 1998-07-06 23:50:00
Subject: PRO> Pertussis - USA: Review, case study & comment
Archive Number: 19980706.1270
PERTUSSIS - USA: REVIEW, CASE STUDY & COMMENT
*********************************************
A ProMED-mail post
<http://www.healthnet.org/programs/promed.html>
See Also
Pertussis - USA (Arizona) 980628092738Pertussis - USA (Arizona) (02) 980701002624
Pertussis - USA (California) 980705111826
Date: Mon, 6 Jul 1998 16:18:51 -0600
From: Kevin Johnson <kevin@johnsonk.hd.co.harris.tx.us>
Pertussis is a much larger problem in this country than you think. Vaccine
efficacy wanes after 7 years so almost anyone over the age of 14 is
susceptible. The following is a true case surveillance report from Harris
County, Texas.
General Practitioners and all doctors need to be ever vigilant about
pertussis because you are more likely to see the adult cases than
Pediatricians are to see it in children. I challenge you to look at the
CDC case definitions and see how many cases you have seen that fit.
Recognition of adult cases (that maintain a reservoir); treatment of cases
an appropriate prophylaxis of contacts will complete the circle of
prevention that begins with appropriate vaccine coverage.
The case:
A 30 year-old pregnant white female presents to her doctor with a cough of
3 weeks duration and "coughing fits" (paroxysms of coughing). The doctor
tells her that she does not have a fever (pertussis rarely does) and
probably has that upper respiratory virus that is going around and sends
her home. 2 days later she gives birth and the newborn subsequently
develops a cough at 3-days of age and paroxysmal coughs at 6 days of age .
She takes the child to the hospital and the attending pediatrician states
that he has the "crud" that is going around and starts to leave. At that
time the doctor hears that inspiratory whoop and quickly states "Oh my god!
I am glad I heard that!". He proceeds to change the diagnosis, collect
culture samples and to prescribe antibiotics for the patient only, and
[then releases the infant to home. The child was later hospitalized
following an episode of apnea and recovers.
Seven confirmed cases were discovered through the investigation of this
laboratory-confirmed case. Prophylaxis of contacts of confirmed cases is
the standard of care in the United. No one was prophylaxed (given
preventative antibiotics) until the health department became involved.
Recommended Action:
Anytime that a person calls or comes into your office and meets the
clinical case definition of pertussis (see below) it should reported to
the health department. These patients are classified as probable cases and
all household and close contacts should be prophylaxed with Erythromycin,
Clarithromycin, other macrolides, or trimethoprim-sulfamethoxazole (1).
Nasopharyngeal swab specimens should be taken and the laboratory should be
called and informed of the type of culture that you are requesting (1).
This organism is difficult to grow, negative cultures are common and more
often than not the diagnosis must be made on clinical presentation and
judgment.
Both probable and confirmed cases should be reported to the local health
Department.
Additional information:
Pertussis is a pervasive problem in the United States. In the days before
the vaccine was available this was major problem in children and the term
"Whooping Cough" was assigned to it as a description of the inspiratory
whoop that is characteristic of this disease. Unfortunately this
characteristic sign is often lacking in adults with the disease. CDC uses
the following [definitions.
Case Definitions:
Clinical case definition: A cough illness lasting at least 2 weeks with one
of the following: paroxysms of coughing, inspiratory "whoop," or
post-tussive vomiting -- and without other apparent cause (as reported by a
health professional).
Laboratory criterion for diagnosis: Isolation of Bordetella pertussis from
clinical specimen
Case classification:
Probable: meets the clinical case definition, is not laboratory confirmed,
and is not epidemiologically linked to a laboratory-confirmed case
Confirmed: a clinically compatible case that is laboratory confirmed or
epidemiologically linked to a laboratory-confirmed case
Comment:
The clinical case definition above is appropriate for endemic or sporadic
cases. In outbreak settings, a case may be defined as a cough illness
lasting at least 2 weeks (as reported by a health professional). Because
direct fluorescent antibody testing of nasopharyngeal secretions has been
shown in some studies to have low sensitivity and variable specificity
(2,3), it should not be relied on as a criterion for laboratory
confirmation.
In a recent study in JAMA 153 serologically confirmed cases of pertussis
that had a long lasting cough (avg. duration 6 wks) were all misdiagnosed
when what they had was pertussis (4). None of the patients even had
pertussis listed as a possibility in the suspect or differential diagnosis
lists (4). The rate of disease reported in this article was 176 cases per
100,000 per year. This would mean that Harris County excluding the city of
Houston should see approximately 2,077 cases of pertussis per year. In
1997 there were 21 cases reported, but how many more were not reported or
not diagnosed?
Pertussis in adults is still the reservoir that perpetuates this disease.
Why? That is simple, vaccine efficacy wanes after 7years and the last
vaccines are given at age 7 due to the increase in side effects.
References:
1. American Acadamy of Pediatrics Report of the Committee on Infectious
Diseases 24th ed. p. 397.
2. Boome CV, Fraser DW, English WJ. Pertussis diagnostic methods and
surveillance. In: Manclark CR, Hill JC, eds. International Symposium on
Pertussis. Bethesda, Maryland: National Institutes of Health, 1978;19-22.
3. Halperin SA, Bartolussi R, Wort AJ. Evaluation of culture,
immunofluorescence and serology for the diagnosis of pertussis. J Clin
Microbiol 1989;27:752-7.
4. Nenning ME., Shinefield HR, Edwards KM, Black SB, Fireman BH. Prevalence
and incidence of adult pertussis in an urban population., JAMA.
275(21):1672-4, 1996 Jun 5.
--
Kevin Johnson
Epidemiologist/Data Analyst
Harris County Health Department
e-mail: kevin@johnsonk.hd.co.harris.tx.us
[1995 CDC estimates of DPT vaccine coverage for Houston Texas report a
range of from 61-70%. Reference: National Center for Health Statistics;
Assessment Br, Data Management Div, National Immunization Program,
CDC. - Mod.ES
...........................................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.
############################################################
############################################################