REPORT OF THE MANAGER

     August 2017

 

 

I.       Water and Weather

 

The National Weather Service, Hanford reported temperatures in August had an average high of 98°F and an average low of 68°F.  Eleven of the days climbed to or above 100°F.  The thirty-year average high and low for August is 93°F and 65°F respectively. Water storage levels at Pine Flat Reservoir was recorded at 712,892 acre-feet by the end of the month, approximately 185,000 acre-feet less that the month of July.  Inflow was 1,508 cubic feet per second (CFS) and release was 4,557 CFS.  Lake Kaweah Reservoir water storage was recorded at 17,351 acre-feet at the end of the month, approximately 85,500 less acre-feet than storage levels in July.  The inflow and outflow were 179 CFS and 679 CFS respectively.

 

II.    Narrative

 

The Delta Vector Control District laboratory staff continued to monitor WNV activity in mosquito populations using both gravid and CO2 traps. All suburban areas of the district were routinely surveyed with 172 gravid traps a week. Laboratory staff set approximately 10 CO2 traps a week to monitor mosquito activity in rural and agricultural areas.  Mosquito abundance in suburban areas remained relatively constant with an average of 15 mosquitoes recorded per trap-night throughout the month of August. Continued monitoring of the kiwi farms in NE Dinuba revealed a gradual reduction in trap counts, as of August 31st, the average trap count was 170 mosquitoes per trap as opposed to +1,000 mosquitoes per trap at its peak. West Nile Virus (WNV) screening continued and as of September 1st, 552 mosquito collections had tested positive for WNV out of 2,548 pools tested.

 

In order to combat the newly discovered invasive Aedes aegypti mosquitoes a sanitation and public education campaign was initiated in the city blocks with trap-sets containing the greatest number of Aedes aegypti mosquitoes. As of September 6th a total of 268 property inspections had been completed on 158 properties. Out of the 158 properties inspected, 37 properties were found to be breeding Aedes aegypti, 23% of total inspections. All property inspections included: breeding site investigations, breeding site sanitation with a 10% bleach solution (where required) and home-owner education on how to reduce mosquito breeding. In addition, 156 of the 158 properties were barrier-treated with deltamethrin to knock down mosquitoes resting in vegetation.

   

 

 

 

Dairy treatments have increased during August due to corn being harvested. With pit water levels coming up, less new weed growth needs to be treated, so the Weed Crew has been utilized to keep the Catch basin treatments up to date. Deliveries of ditchwater from the Kaweah and St. Johns River’s ended the last week of August. Alta Irrigation is still making water deliveries from the Kings River system and is to continue through September. Field Technicians are busy with pre-harvest irrigation of prune, almond and walnut orchards as well as their regularly treated sites. Work hours for all employees went back to 7:30am to 4:00pm following Labor Day.

    

There were thirty-nine service requests during the month categorized as follows:

 

2017 Service Request Summary

                                                                                                                                   

 

Fish

Inspection

Mosquito

Source

Other

Total

January

0

0

0

0

0

  0

February

1

4

0

0

2

7

March

8

11

1

18

8

46

April

7

13

6

17

4

47

May

6

20

0

18

1

45

June

3

20

4

4

1

32

July

0

4

2

3

0

9

August

0

13

12

13

1

39

Total

25

85

25

73

17

225

           

·         Five of the twelve mosquito service requests were related to invasive Aedes aegypti mosquitoes

 

III. Vector and Disease Surveillance

 

Delta VCD Summaries

           

Humans: Of the three suspect West Nile Virus cases previously reported to the District, two have been confirmed by the California Department of Public Health. The third suspect case is still pending and awaiting confirmation.

 

No additional Aedes-born disease cases (Zika, Dengue, Yellow Fever, Chikungunya) were reported to the District.

 

Birds: Ten dead birds were reported within Tulare County. One bird met the requirement for WNV testing and did not test positive for WNV.

 

Mosquito: A total of 1,110 traps were set among all trap types. This is 28 more traps set than last month. A total of 614 mosquito pools were tested with 196 pools testing positive for WNV and 12 testing positive for SLEV. The following graphs compare 2017 and 2016 gravid trap counts to date, as well as the WNV infection rate in mosquitoes, reported as percent positive.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The invasive Aedes surveillance program set a total of 231 Aedes specific traps in the month of August. The traps consisted of those that target oviposition seeking mosquitoes AGO’s (155), as well as those that target host seeking mosquitoes BGS (76). AGO traps were used in routine surveillance (1 per square mile of populated area within District boundaries) BGS traps were placed in response to service requests and surveillance of a newly detected population of Aedes aegypti mosquitoes in Visalia.

 

As of August 31st eighty-four Aedes aegypti had been collected from 33 locations and 76 BG trap-sets. None of the AGO trap sets recovered an Aedes aegypti mosquito. Aedes aegypti trap counts in BG traps ranged from 1-14 mosquitoes collected per trap-set. The population of invasive mosquitoes was first discovered after following up a travel-related Zika case. Mosquito specimens sent to UC Davis for Zika virus testing have been confirmed negative.

 

State Surveillance:

Humans: As of September 1st 2017, 79 new human cases of WNV were reported by the California Department of Public Health (CDPH) from numerous counties throughout CA. This is a 10-fold increase from the number of human cases reported last month. To date this year 87 cases of WNV have been reported, 77% of the cases with neuroinvasive disease. At this time in 2016, 123 human cases had been reported.

Birds:  As of September 1st 2017, 264 birds have been reported positive for WNV to CDPH. In comparison at the end of July 2016, 1,137 birds had been reported positive. 

Mosquitoes:  As of September 1st 2017, 2,545 mosquito pools have been reported positive for WNV by CDPH from 24 counties. In comparison, at this time last year, 2,939 mosquito pools had tested positive from 30 counties. In addition, 70 mosquito pools have tested positive for SLEV to date, from 11 counties.

 

IV. Expenditures & Revenues – 2017/18

 

            TOTAL BUDGET                                          $4,205,079.78

 

EXPENDITURES – July 1 – August 31, 2017

Salaries

$640,194.60

Services & Supplies

$173,257.96

Tax Admin Fee

 

Capital

$1,513.44

Long-Term Debt

 

TOTAL EXPENDITURES

$814,966.00

             

            REVENUE RECEIVED – July 1 – August 31, 2017

July

$533.21

August

$158.70

TOTAL REVENUE TO DATE

$691.91

           

           

V.    Time Sheet Summary                      

       

Month

Available Work Hrs

Sick Hrs Used

Total Hrs Available for Work

Pct. Of Hrs Avail for Work

July

4320

66.50

4253.50

98.46

August

4600

30.75

4569.25

99.34

 

The District has a vacation policy that requires 24 hour notice in order to ensure the operational integrity of the workforce.  Sick leave for doctor, dentist and/ or family medical necessity also requires advance notice- in so much as it is possible.  Illness is unplanned and therefore unscheduled.  Attendance records for the current year are shown in the table.