I was reading about the various influenza strains since 1900, and came upon this article about the first cases of re-emerging H1N1 at the Ft. Dix military base in 1976. Read about the testing, especially their results with soldiers who had an H3N2 VAX - cross reactive immunity! (sorry folks, I've been beating this drum for almost a year now).
http://www.flu.org.cn/en/article-3874.html
(snip) (A/Mayo Clinic is H1N1)
Case Finding at Fort Dix
Case-finding was conducted prospectively and retrospectively (Table). Prospectively, throat washings were collected from patients with febrile, acute respiratory disease who were hospitalized or sought treatment at the emergency room February 14?16 (phase I, n = 50) and February 22?24 (phase II, n = 45) (7). Attempts were made to obtain paired serum specimens from phase I patients. Specimens were obtained from 60 basic training soldiers, 13 other military personnel, and 22 civilians. A/Victoria/75 (H3N2) virus was isolated from 34 (68%) persons during phase I and 21 (47%) in phase II (7). A/New Jersey/76 (Hsw1N1) was not isolated from any of the 95 patients. One of 34 (3%) persons with an A/Victoria isolate and paired serum samples had a >4-fold rise in titer to A/Mayo Clinic (Hsw1N1) antigen, with an acute titer of <1:10 increasing to 1:20 (7).
Retrospective study was made possible by an ongoing Adenovirus Surveillance Program, which collected weekly throats swabs and paired serum specimens from a sample (≈3%?6%) of basic trainees hospitalized with respiratory disease (7). Specimens had been sent to Army regional laboratories, and 80% of the paired serum specimens from Fort Dix trainees hospitalized between November 1, 1975, and February 14, 1976, went to Fort Meade, Maryland. Serum specimens not depleted by routine studies were stored. Stored serum specimens from 74 Fort Dix trainees were identified at Fort Meade and forwarded to WRAIR; 39 (53%) of the trainees had been hospitalized after January 1, 1976. These serum samples were initially tested against A/Mayo Clinic antigen. Serum samples with >4-fold rises in titer were re-tested against A/New Jersey and A/Victoria/3/75 (H3N2) antigens (7). HAI titers to A/Mayo Clinic and A/New Jersey differed only slightly.
Concerns that influenza A (H3N2) infection or vaccination might stimulate antibody to A/Mayo Clinic were addressed. Four groups were studied to identify persons with >4-fold heterotypic HAI antibody increases to A/Mayo Clinic. None were found in 39 Fort Dix soldiers who received influenza vaccine in February 1976 (group 1), and none were found among 27 hospitalized soldiers from posts other than Fort Dix who had >4-fold rises in complement fixation (CF) antibody to influenza A (group 2) (7). In the third group, >4-fold rises in antibody titers developed in 3 (8%) of 40 soldiers from Fort Dix and elsewhere who had been hospitalized with an A/Victoria isolate (7). In the fourth group, a single serum sample was studied from each of 168 randomly selected Fort Dix basic trainees who had received their annual influenza vaccination 3 to 4 weeks earlier (11). Only 4 (2%) had HAI titers >1:20 to A/Mayo Clinic (11). In similar studies by others, in 0%?6% of persons, heterotypic antibody to influenza A/swine developed after infection with A/Victoria (H3N2) or influenza vaccination (12,13).
Since heterotypic antibody to A/Mayo Clinic seldom occurred, soldiers who were hospitalized for acute respiratory disease and showed a >4-fold titer rise to influenza A (Hsw1N1) in stored serum specimens from the Adenovirus Surveillance Program were considered to have had A/New Jersey infections. Eight new cases in basic trainees were found. Three (38%) of the 8 solders also had >4-fold antibody rises to A/Victoria. Therefore, 13 male, enlisted soldiers, aged 17?21 years, were identified as having had respiratory diseases resulting in hospitalization or death and an A/New Jersey (Hsw1N1) isolate or serologic conversion to A/New Jersey (case-patients). Ten had arrived at Fort Dix between January 5 and February 3, 1976. Three arrived between September 9 and December 30, 1975. Dates of onset of illness were known for 12 and were from January 12 to February 8, 1976. Hospital admissions occurred between January 19 and February 9. Autopsy findings for the only patient who died showed severe edema, hemorrhage, and mononuclear infiltrates in the lungs, consistent with viral pneumonia. No preexisting disease or bacterial infection was found. Four (33%) of the 12 surviving patients had radiologic evidence of pneumonia but their clinical syndromes were similar to those described for patients with infections caused by other influenza A strains (7).
(snip)
http://www.flu.org.cn/en/article-3874.html
(snip) (A/Mayo Clinic is H1N1)
Case Finding at Fort Dix
Case-finding was conducted prospectively and retrospectively (Table). Prospectively, throat washings were collected from patients with febrile, acute respiratory disease who were hospitalized or sought treatment at the emergency room February 14?16 (phase I, n = 50) and February 22?24 (phase II, n = 45) (7). Attempts were made to obtain paired serum specimens from phase I patients. Specimens were obtained from 60 basic training soldiers, 13 other military personnel, and 22 civilians. A/Victoria/75 (H3N2) virus was isolated from 34 (68%) persons during phase I and 21 (47%) in phase II (7). A/New Jersey/76 (Hsw1N1) was not isolated from any of the 95 patients. One of 34 (3%) persons with an A/Victoria isolate and paired serum samples had a >4-fold rise in titer to A/Mayo Clinic (Hsw1N1) antigen, with an acute titer of <1:10 increasing to 1:20 (7).
Retrospective study was made possible by an ongoing Adenovirus Surveillance Program, which collected weekly throats swabs and paired serum specimens from a sample (≈3%?6%) of basic trainees hospitalized with respiratory disease (7). Specimens had been sent to Army regional laboratories, and 80% of the paired serum specimens from Fort Dix trainees hospitalized between November 1, 1975, and February 14, 1976, went to Fort Meade, Maryland. Serum specimens not depleted by routine studies were stored. Stored serum specimens from 74 Fort Dix trainees were identified at Fort Meade and forwarded to WRAIR; 39 (53%) of the trainees had been hospitalized after January 1, 1976. These serum samples were initially tested against A/Mayo Clinic antigen. Serum samples with >4-fold rises in titer were re-tested against A/New Jersey and A/Victoria/3/75 (H3N2) antigens (7). HAI titers to A/Mayo Clinic and A/New Jersey differed only slightly.
Concerns that influenza A (H3N2) infection or vaccination might stimulate antibody to A/Mayo Clinic were addressed. Four groups were studied to identify persons with >4-fold heterotypic HAI antibody increases to A/Mayo Clinic. None were found in 39 Fort Dix soldiers who received influenza vaccine in February 1976 (group 1), and none were found among 27 hospitalized soldiers from posts other than Fort Dix who had >4-fold rises in complement fixation (CF) antibody to influenza A (group 2) (7). In the third group, >4-fold rises in antibody titers developed in 3 (8%) of 40 soldiers from Fort Dix and elsewhere who had been hospitalized with an A/Victoria isolate (7). In the fourth group, a single serum sample was studied from each of 168 randomly selected Fort Dix basic trainees who had received their annual influenza vaccination 3 to 4 weeks earlier (11). Only 4 (2%) had HAI titers >1:20 to A/Mayo Clinic (11). In similar studies by others, in 0%?6% of persons, heterotypic antibody to influenza A/swine developed after infection with A/Victoria (H3N2) or influenza vaccination (12,13).
Since heterotypic antibody to A/Mayo Clinic seldom occurred, soldiers who were hospitalized for acute respiratory disease and showed a >4-fold titer rise to influenza A (Hsw1N1) in stored serum specimens from the Adenovirus Surveillance Program were considered to have had A/New Jersey infections. Eight new cases in basic trainees were found. Three (38%) of the 8 solders also had >4-fold antibody rises to A/Victoria. Therefore, 13 male, enlisted soldiers, aged 17?21 years, were identified as having had respiratory diseases resulting in hospitalization or death and an A/New Jersey (Hsw1N1) isolate or serologic conversion to A/New Jersey (case-patients). Ten had arrived at Fort Dix between January 5 and February 3, 1976. Three arrived between September 9 and December 30, 1975. Dates of onset of illness were known for 12 and were from January 12 to February 8, 1976. Hospital admissions occurred between January 19 and February 9. Autopsy findings for the only patient who died showed severe edema, hemorrhage, and mononuclear infiltrates in the lungs, consistent with viral pneumonia. No preexisting disease or bacterial infection was found. Four (33%) of the 12 surviving patients had radiologic evidence of pneumonia but their clinical syndromes were similar to those described for patients with infections caused by other influenza A strains (7).
(snip)
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