Streptococcus suis meningitis in weaners

Note this is a zoonotic pathogen – can infect man. Ensure staff wash hands using soap after handling affected pigs. Cover all cuts and abrasions on the hands and arms.

Investigation of a problem on a farm - checklist

Treatment of an individual which is recumbent, fitting or comatose
	Remove from group			Place in hospital area without other pigs while fitting
	Inject with ceftiofur sodium 3mg/kg – this is 3x higher than normal dose
	Inject with a pain killer - Meloxicam 0.4 mg/kg for example
	Reduce light levels
	Provide water by mouth
	If no response within 24 hours euthanase
Treatment of the group
	Review the cost of treatment of the group vs. individual. Individual cases best treated individually, but may represent the beginning of an outbreak
	Amoxycillin in the water supply for 3 days post-weaning. Amoxycillin can be difficult to dissolve.
	Tetracycline in-feed from weaning to 18kg at a rate of 800ppm.
	Inject all pigs at weaning with ceftiofur crystalline free acid (Excede 3 mg/kg)
Investigation into an “outbreak” – sudden increase in cases on a farm within a pen
Immediate	Check for PRRSv		Especially in a negative PRRSv herd
			Check for PRRSv in other pigs – conjunctivitis for example
	Check for PMWS/PCVAD		Ensure that the pigs were vaccinated at weaning – PCV2 Check vaccine purchases correspond to weaning numbers Check medicine storage – 2-8°C
	Post-mortem		Ensure diagnosis correct – differentials: Glässer’s and Bowel Oedema. Gram stain on meninges/brain histology. Bacteriology: Note isolation of Strep. suis II normal in most pigs. Take cerebral spinal fluid. Type the Strep suis – other strains may be a problem 1½ and 14 for example
	Check weaning age and weight		Average and variance. Check number of litters below 17 days of age and number of litters which are from gilts. Piglets weaning below 5 kg should be looked for.
			If problem also in farrowing area – check colostum intake
	Check pig flow and all-in/all-out
	Check water flow		700 mls per minute. One nipple drinker per 10 pigs
	Check temperature		At entry into nursery – 30°C Examine cooling curve, looking for sudden changes – power failure etc. Record weaner lying and defecation patterns
	Examine clean building prior to entry		Particularly check that room is dry Room is warm Room will not sweat
Medium	Tag/mark piglets		Gilt litters and (differently) small piglets at weaning
Long term	See “long term” problem investigation – eliminate all negative stressors on the pig post-weaning
Investigation of “long term” problem
Streptococcus suis meningitis is a stress induced problem. It is normal for the pig to be “infected” by 6 weeks of age nearly 100% of pigs in a group will be carriers
`	Pig flow and all-in/all-out	Review adherence to the pig flow programme. Nursery pigs need 0.3 m^2 per pig (to 30 kg) Total volume should be checked also – 0.8m^3 per pig
	All-in/all-out	AIAO by pigs, water, feed, floor, air and medicine. Ensure needles and syringes not used between different groups. Add lime-washing to the cleaning protocols
		Keep needles and syringes specifically for meningitis treatment
	Tools, Foot baths, clothing.	Run a batch concept for all equipment between rooms. Wear different footwear between rooms
		All staff to wash hands with soap after handling affected pigs
		Staff to wash hands with soap between batches
		Recovered pigs are not to return to younger group of pigs
	Mortality and morbidity	Examine the mortality figures by batch Examine the morbidity figures by batch and age Examine the records using statistical process control – many “outbreaks” are not real just part of natural variations
	Feed-back programme	Feed back programme to gilts in isolation and sows 6 weeks pre-farrowing. Use faeces from 10 day weaned pigs and from “affected” age groups
	Temperature	Review temperature cooling curve
		Monitor curve with a remote sensor logger Ideal 30°C entry, cooling 1°C per week to 24°C
	Heating system	Gas heating – check colour of flame and CO concentrations
		Many farms with a meningitis problem staff have “headaches”
	Air pollutants	High dust, endotoxin and humidity (>75%RH) need eliminating
		Note level of slurry under slats – air flow from underneath slats
	Air flow	Eliminate all draughts in the “proposed sleeping area”
		Examine defecation pattern of pigs
		Examine and record lying pattern of undisturbed pigs
		Smoke buildings.
	Water supply	Ensure sufficient water supply –Observe weaner’s behaviour regarding drinkers. Water flow 700ml. One nipple drinker per pig, one bowl drinker per 20 pigs. Check height of drinkers
		Ensure clean between batches
		OxySan or Vircon S during outbreak
		pH of water post-weaning
	Feed	Observe weaner’s behaviour regarding feeding
		Record feed space (50 mm per pig 30 kg) and feeder management
		Increase Vit E – 250 mg/kg and possibly Vit C
		Review feeding and management of weaners immediately post-weaning
		Adopt a gruel feeding regime 3-4 days post-weaning
		Note if the time of problem coincides with a change in diet/feed type and feed size
	Vaccine programme	Consider Strep. suis autogenous vaccine programme. Some commercial vaccines are available but response can be variable.
	Eliminate other problems	PRRSv, PCVAD/PMWS and Mange are classical examples of problems.
		Eliminate any additional stressors at weaning – weighing, tagging, bleeding etc.

Checklist to help the investigation