The Lawrence-Douglas County Health Department on Friday released the following timeline of its cryptosporidium investigation and actions taken in alerting the public.
(See earlier story.)

TIMELINE OF CRYPTOSPORIDIUM INVESTIGATION ACTIVITIES

JULY 24
¢ Lawrence-Douglas County Health Department (LDCHD) received notification of a confirmed cryptosporidium case (CASE #1) in a swimmer of team A, who had been experiencing diarrhea for 12 days beginning 7-09-03.
¢ LDCHD checked with several primary care physician offices and the hospital emergency room regarding increased reports of diarrhea. None indicated increased reports of diarrhea among their patients.
¢ LDCHD notified Kansas Department of Health and Environment (KDHE) and discussed the possibility of the spread to others. Consultation between LDCHD and KDHE continued virtually daily throughout the investigation.

JULY 25
¢ LDCHD received anecdotal reports of other members of team A with diarrhea. LDCHD notified swim coach of team A and advised coach not to allow any symptomatic members to compete or swim. Coach agreed to pull symptomatic members.
¢ LDCHD learned that swimmers from team A were swimming and training with the team B during the summer session. Anecdotal report from coach of team A revealed that other swimmers on team B had experienced symptoms of diarrhea.
¢ LDCHD mailed a letter to all members of team B, informing them of a confirmed cryptosporidium case identified in a person associated with team B. The letter requested to contact LDCHD for the purpose of diarrheal surveillance and identify other symptomatic individuals. The letter also advised swimmers to contact their physician if they had symptoms of diarrhea. Cryptosporidium fact sheet was attached for additional information.

JULY 27
¢ LDCHD met with swimmers of team A (that was associated with case #1) who had been training together during the summer (n=11). The 7-day enteric questionnaire was administered, and 10 stool sample kits were distributed (seven of which were returned in the following days).

JULY 28
¢ LDCHD received phone calls in response to letter sent to team B. No cases of cryptosporidium were confirmed among members of team B.
¢ LDCHD faxed information to Douglas County physicians: pediatricians, family practice, general practice, internists, pathologists, KU student health, Haskell health center, Baker University student health, two urgent care centers, the hospital and emergency room.
¢ LDCHD was notified later in the day of CASE #2, who had diarrhea between July 8 — July 22.

AUGUST 1
¢ LDCHD received positive result on CASE #3, one of the team A swimmers who received stool kits on July 27.
¢ LDCHD received positive results on CASE #4, a child whose interview later revealed to be associated with summer camp A, and on CASE #5, whose interview later revealed no exposure to pools or day cares.

AUGUST 4 THROUGH 6
¢ Interviews are completed with all confirmed cases so far and information is reviewed.

AUGUST 7
¢ LDCHD learned of CASE #6, a child at day care facility A. Preliminary investigation revealed that 17 of the 22 children associated with case #6 had had diarrhea. All had also swum in a plastic wading pool.
¢ LDCHD and KDHE recommended that children with current symptoms of diarrhea consult a physician and obtain a stool tests. As a result several stool testing kits are distributed.
¢ Inspection of day care facility was made to stress hand washing and disinfection of toys. The wading pool was believed to be a likely source of transmission and its use was discontinued.
¢ LDCHD sent another fax to physicians to inform them of CASE #6. Memo also informed physicians that families of children would receive information about cryptosporidium and would be advised to notify physicians if symptoms developed. Letter discussed that an epidemiology investigation was being conducted to identify additional cases.
¢ LDCHD distributed a letter to the parents of all day care facility A members informing them of CASE #6. Symptoms and recommendation to contact physicians with symptoms were discussed. Parents were also informed that children with symptoms should not attend day care. A fact sheet on cryptosporidium was attached.

AUGUST 13 THROUGH 14
¢ LDCHD notified of CASE #7, 8, and 9, all children in day care facility A.

AUGUST 18
¢ LDCHD notified of CASE #10, 2nd positive case summer camp A (see case #4).
¢ A fact sheet on cryptosporidium was sent to director of summer camp A.
¢ KDHE contacts CDC’s Division of Parasitic Diseases for consultation.

AUGUST 20
¢ LDCHD notified of CASE #11, a positive case in day care facility B.

AUGUST 21
¢ LDCHD distributed a letter to the parents of all day care facility B members informing them of CASE #11. Symptoms and recommendation to contact physicians with symptoms were discussed. Parents were also informed that children with symptoms should not attend day care. A fact sheet on cryptosporidium was attached
¢ LDCHD and KDHE discuss plan of action during phone consultation.

AUGUST 22
¢ LDCHD faxed another letter to physicians to inform them of the 11 positive cases. Physicians were advised to test for cryptosporidium and to report to the LDCHD any increase in diarrheal illness.
¢ There are now 11 cases, 8 of which in children.
¢ Ten of the eleven cases report swimming in a number of swimming pools in the two weeks prior to symptoms. Most cases have also exposure to at least one additional risk factor, such as attendance to a day care facility or close contact with other individuals with diarrhea.
¢ Due to very hot conditions, it is likely that a large number of people, if asked, would report that they used a swimming pool in the previous two weeks. Therefore the swimming history from the cases is difficult to interpret.
¢ Joint conference call held with LDCHD, KDHE and CDC. The increased number of cases, and the fact that the last several cases are not apparently associated with any one day care facility or institution, raise the concern that the disease is spreading throughout the community. Options for action discussed, including gathering additional information to better understand the possible role of swimming pools in the outbreak. Although there is no definite evidence that the swimming pools were at the origin of the outbreak, there is a concern that now that the outbreak is more widespread swimming pools could act as amplifiers and facilitate transmission of the infection. A decision was made, therefore, to immediately target swimming pools for disinfection and disease control activities.
¢ LDCHD required hyper-chlorination of two pools (Alvamar and City of Lawrence Outdoor pool) and because lacked legal jurisdiction to order action, recommended hyper-chlorination of two other pools (Haskell and KU). The City of Lawrence Indoor pool (Free State) had already been drained and closed for unrelated reasons.
¢ The four pools closed to hyper-chlorinate. LDCHD monitored the testing results.
¢ LDCHD distributed news release about the cryptosporidium outbreak and the closing of Lawrence pools for hyper-chlorination. News release also discussed the epidemiology investigation being conducted to identify the possible source. Release advised that anyone with diarrhea and immuno-compromised individuals should avoid swimming.
¢ LDCHD mailed a letter to all daycare facilities (n=300) informing them of the number of cases and the epidemiologic investigation. Exclusion guidelines were discussed. Providers advised to contact LDCHD child care licensing staff for questions and to report increased incidence of diarrheal illness to LDCHD.
¢ LDCHD faxed additional information to Douglas County physicians regarding hyper-chlorination at four community pools and requested that they inform patients with diarrhea (current and for two weeks after diarrhea stops) not to swim.

AUGUST 23
¢ LDCHD issued press release informing public that city pool was cleared to reopen and that health department was working with other pools regarding hyper-chlorination.
¢ LDCHD distributed flyers of public health notice to all four major pools upon reopening to distribute to their patrons. Guidelines were developed and given to pool operators regarding fecal accidents.

AUGUST 24
¢ 55 of 75 pools in Lawrence visited and given a public health notice regarding swimming to display. (By August 27 all 75 pools had been given the public health notice.)

AUGUST 25
¢ CDC and KDHE come on-site at LDCHD to assist with epidemiologic investigation.

AUGUST 27
¢ LDCHD faxed algorithm to Lawrence physicians as a guideline for testing for diarrheal illness.

• Team prepared telephone questionnaire for additional case finding. Case finding is necessary to describe the extent of the outbreak and to identify commonalities among all cases that need to be studied. LDCHD began telephone interviews to members of groups where cases have already been identified. Over 1,600 telephone calls will be made during the following ten days.
  ¢ Team made random selection of four elementary schools for receipt of household diarrheal survey for case finding purposes. LDCHD contacts school officials to get their cooperation.

AUGUST 28
¢ 1,770 copies of household diarrheal survey printed, assembled and distributed with instructions to four local schools.

AUGUST 29
¢ Survey returned form school. Results collated by team.
¢ Of the 1,444 questionnaires distributed, 753 were returned. These surveys contained information on 3,194 individuals. Of these, 221 (7%) reported having experienced diarrhea after June 15th.
¢ Although hard to compare to numbers from other surveys done elsewhere, these results did not seem to indicate a very unusually high number of people with diarrhea in the groups surveyed.
¢ People reporting recent diarrhea were encouraged to submit specimens for laboratory testing.

SEPTEMBER 1 through 12
¢ More cases are diagnosed as a result of the active case finding done in the previous weeks.
¢ Most recent cases are among children, and an increasing number of them are associated with day care facilities.
¢ More aggressive control measures are implemented in day care centers.
¢ A large case control study, including several hundred interviews, is planned. Both sick and non-sick people will be interviewed by phone. Questions about their exposure to swimming pools, lakes, food, animals, other people sick with diarrhea, etc. will be asked. The study will be completed in about 4-6 weeks, and preliminary analysis of the data should be available after a couple of weeks from the completion. The results will be helpful in indicating possible mechanisms of origin of this outbreak, routes of transmission, and prevention measures for this and future outbreaks.
¢ Case control study starts on September 12.