While there could be such which were undiscovered prior to flu infection, note also the difference in governmental response to the outbreak.
(Thanks, DvdMom, for the ping!)
Most Deaths In 1918 Influenza Pandemic Caused By Bacterial Pneumonia
8/20/2008
http://www.medicalnewstoday.com/articles/118727.php
Quote:
The majority of deaths during the influenza pandemic of 1918-1919 were not caused by the influenza virus acting alone, report researchers from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health. Instead, most victims succumbed to bacterial pneumonia following influenza virus infection. The pneumonia was caused when bacteria that normally inhabit the nose and throat invaded the lungs along a pathway created when the virus destroyed the cells that line the bronchial tubes and lungs
Plus CDC seems to think there is some importance to the connection:
Interim guidance for use of 23-valent pneumococcal polysaccharide vaccine during novel influenza A (H1N1) outbreak
June 9, 2009 2:15 PM ET
http://www.cdc.gov/h1n1flu/guidance/ppsv_h1n1.htm
Quote:
Background
Influenza predisposes individuals to bacterial community-acquired pneumonia. During the 20th century influenza pandemics, secondary bacterial pneumonia was an important cause of illness and death and Streptococcus pneumoniae (pneumococcus) was reported as the most common etiology. Severe pneumococcal pneumonia associated with inter-pandemic influenza also has been reported, and S. pneumoniae remains a leading cause of vaccine-preventable illness and death in the United States. The current novel influenza A (H1N1) outbreak is evolving rapidly, and CDC continues to compile key information regarding risk of influenza, severity of illness and attack rate of secondary bacterial pneumonia among influenza patients. At this time, however, the role of pneumococcal infections among severe cases of novel influenza A (H1N1), such as those requiring hospitalization, is unclear.
Pneumococcal vaccines
During influenza outbreaks, pneumococcal vaccines may be useful in preventing secondary pneumococcal infections and reducing illness and death. Currently, two vaccines are available for prevention of pneumococcal disease, a 23-valent pneumococcal polysaccharide vaccine (PPSV23) and a 7-valent pneumococcal conjugate vaccine (PCV7).