|Year : 1996 | Volume
| Issue : 12 | Page : 335-338
Study of suspected plague cases for isolation and identification of Yersinia pestis
SR Gaval, SN Shrikhande, SK Makhija, NS Tankhiwale, AA Pathak, AM Saoji
Department of Microbiology, Govt. Medical College and Hospital Nagpur440 003., India
|Date of Submission||18-Aug-1996|
S R Gaval
Department of Microbiology, Govt. Medical College and Hospital Nagpur440 003.
|How to cite this article:|
Gaval S R, Shrikhande S N, Makhija S K, Tankhiwale N S, Pathak A A, Saoji A M. Study of suspected plague cases for isolation and identification of Yersinia pestis. Indian J Med Sci 1996;50:335-8
|How to cite this URL:|
Gaval S R, Shrikhande S N, Makhija S K, Tankhiwale N S, Pathak A A, Saoji A M. Study of suspected plague cases for isolation and identification of Yersinia pestis. Indian J Med Sci [serial online] 1996 [cited 2013 May 24];50:335-8. Available from: http://www.indianjmedsci.org/text.asp?1996/50/12/335/11549
Plague was considered to be a highly fatal and devastating epidemic disease for last few centuries. But with the advent of antibiotics it became an almost extinct disease with a few localised foci in certain endemic areas. In india no mortality has been recorded due to plague since last 28 years. , However in year 1994 in the months of September - October it acquired centre stage and was a matter of which debate and discussion in the national and international fora and media causing much concern and consternation. All this resulted in a tremendous impact on the budding economy of our country making the health planners sit up and take a serious note of an otherwise redudant problem. 
The reappearance of plaque resulted in the reactivation of the plague monitoring centre in our hospital also. We present our data of the suspected etpidemic of plague.
| ¤ Material and Methods|| |
We studied a total of 62 suspected patients of plague admitted in the isolation ward of Govt. Medical College and Hospital, Nagpur from September to November 1994. Of these 62 patients, 52 were males and 10 were females. Of these 62 patients 46 had enlarged inguinal lymph node suggesting clinical diagnosis of bubonic plague and 12 were suspected to be of pneumonic plague and remaining four had non-specific lymphadenitis due to infected injuries, boils etc. These cases were investigated for plague by lymph node aspiration, sputum, blood, serum examination and animal inoculation as per guidelines provided by NICD, Delhi.
| ¤ Collection of Specimens|| |
1. Lymph node asporation
Under all ascptic precautions bubo was punctured with hypodermic syringe and exudate withdrawn and collected in two plain sterile bottles for smear and culture respectively. 2. Sputum : Sputum Samples were collected in wide mouthed sterile bottle. 3. Blood Venous blood 8-10 ml was collected under all aseptic precautions and inoculated in blood culture bottle. 4. Serum: Two samples of blood (5 ml) each were collected in two sterile vials from suspected cases (one immediately after admission and one after a gap of two weeks) The sera were seperated and sent to reference centre National Institute of Communicable Disease Bangalore for detection f 1 antibodies against f 1 antigen of plague bacillus.
| ¤ Microscopic Examination|| |
Smears were prepared from bubo exudate, sputum and blood and were fixed in methanol and stained with Gram stain and 5% methylene blue stain and were examined for gram negative Coccobacili with bipolar straining (Safety pin like appearance.)
Culture : Bubo aspirate and sputum, specimens were first inoculated in brain heart infusion broth incubated at 30°-32°C overnight. Blood culture bottles containing blood were also incubated overnight at 32°C. Bubo aspirate, sputum and blood after overnight incubation was inoculated on (1) Blood agar enriched with brain heart infusion base. (2) Mac-conkey Agar.
Inoculated plates were incubated at 32°C for 48-72 hrs and searched for pin point, transparent colonies which become larger and opague after 72 hrs. Smears were pre-pared from colony and stained with Gram stain, 5% methylene blue and examined for plague like bacili.
In highly suspected 9 cases of pneumonic plague guinea pig incoulation was performed.
| ¤ Results|| |
Of the samples from 62 suspected patients of plague, there was no evidence of Yersinia More Details pestis in any of the direct smears examined. None of the samples was positive for Y. pestis by culture and serology. Of the samples from 62 patients all the 4 samples (L. N. aspirate + Blood + Sputum + Serum) were received and processed in. 3 patients only. In 9 patients only 3 samples (Blood + Sputum + Serum) were received. In 7 patients only 2 samples (Blood + Serum) were received. Of the 62 blood specimens, 48 showed nogrowth (77.41%), of the 46 lymph node aspirates 38 showed nogrowth nogrowth (82.6%) and of the 12 sputum samples 8 showed no growth (75%). The exact break up of different samples, number of samples showing growth and and the isolates and their number is shown in the [Table 1].
All inoculated guinea pigs remained healthy for the duration 72 hours after inoculation.
| ¤ Discussion|| |
The arrival of plague in the Beed district of Maharashtra state in the month of August and subsequently it's appearance in Surat in Gujarat in September 1994 took general public and health authorities totally unaware. That an epidemic may arrive in a big way in the earthquake hit areas of western Maharashtra was predicted  but what was not imagined at all was the fact that it may be an almost for gotten disease like plague. Though no major outbreak of plague has been reported since 1967 onwards, it is a well known fact that plague cycle is maintained in wild nature by rodent - ratflea - rodent cylcle. Usually due to major upheaval, natural cycle gets broken and the domestic rats may be infected by wild rodents as in the case of an earthfquake.
Of the 5150 suspected pneumonic and bubonic plague cases reported during August 26 to 5th September 1994, 53 deaths were reported from 8 states of India. By Oct. 5 only 167 of these cases were confirmed by serology.  The crude case fatality ratio works out to 1%. Of all the cases that we have investigated, none was smear, culture and serologically positive. Blood culture was positive for staphylococci in 8 patients. Staphylococcal septicaemia is an accepted clinical entity and may be responsible for clinical symptoms. Chances are that in the highly charged atmosphere the cases were overdiagnosed. About 28 years back the last confirmed case of human plague was reported in our country from Kolar district in Karnataka. Subsequently two outbreaks were reported. One in Tangnu in Himachal Pradesh in 1983 where 17 persons died and ether in Dharampuri in south India in May 1984.  The earthquake affected area was known to be endemic for rodent plague and findings of NICD researchers for the last five years that the rodents in South India are seropositive for Y. pestis,  indicates the epidemic to be of Plague. But totally reliable data is as yet unavailable and the very low crude case fatality ratio suggests otherwise.
Our own data also does not corroborates with the suspected clinical diagnosis of plague. But as of now it appears that probably many of the patients diagnosed to be suffering from plague were not true cases. Alternatively early antibiotic therapy in practically all the cases may have altered the course of disease.
| ¤ Summary|| |
A total of 62 suspected patients of plague were investigated for evidence of Yersinia pestis More Details, by blood culture, lymph node aspirate culture, sputum culture, animal inoculation and serology for f 1 antibodies against f 1 antigen of Yersinia pestis. None of the samples was positive by direct smear examination and culture for Yersinia pestis, as well as for serology. The non positivity of the cultures is discussed.
| ¤ References|| |
|1.||Sanjay Kumar. Plague in India. Lancet 1994;344:941-942. |
|2.||Mukhopadhyay SP. Return of plague. JIMA 1995;93:1-2. [PUBMED] [FULLTEXT] |
|3.||Jacob John T. Learning from plague in India. Lancet 1994;344: 972. |
|4.||Sanjay Kumar. Health of Indian earthquake survivors. Lancet 1994; 344:466. |
|5.||Update : Human Plague - India. 1994. JAMA. 1994.272:1320. |