P

Pan flu

It's all right to use the term pan flu after a first reference to pandemic influenza.
Two words, no hyphen.

Parentheses

State names
When inserting a state name into a proper noun such as the South Bend Tribune, put the state name in parentheses.

South Bend (Ind.) Tribune.

Lists in copy
Use parentheses to enclose numbers marking a division within running text.

You will qualify for admission if you are (1) a high school graduate, (2) meet test requirements, and (3) have completed the college preparatory subject requirements.

No colon is necessary before the list, as in the example above.

Pathogens

See bacterium, bacteria.
See fungus, fungi.
See helminths.
See protozoan, protozoa.
See virus, viruses.

Peer review

As a noun, we write peer review without a hyphen.

The data are now turned over to peer review.

As an adjective, we write peer-review with a hyphen.

That study did not go through the proper peer-review process.

Percent

When to spell it out
Write out the word percent in text but use the % sign in charts, scientific copy, and headlines. Percentages should always be represented by a numeral.

[in running copy/text]: an increase of 4 percent
[in headline, chart, press release]: Board Grants 4% Raise

Ranges of numbers
In a range of percentages, use percent after each number.

Anywhere from 20 percent to 40 percent were injured.

Periods

One space after a period
Put only one space after a period (or a colon)—two spaces is a holdover from typewriter days.

Periods and quotation marks
Periods go inside quotation marks.

Periods and abbreviations and acronyms
Do not use periods after the letters of most abbreviations and acronyms.

DrPH, HIV, AIDS, CDC, UN, WHO

Exceptions:
the U.S. government
Washington, D.C.

Periods and initials in a name
When using a person’s initials, use periods. do not put spaces between the initials.

B.F. Skinner
D.A. Henderson

Philippines, the

When referring to Republic of the Philippines in copy, use the Philippines ...

Manila is the capital of the Philippines.
Islam was brought to the Philippines from Malaysia and Indonesia.

... unless it is modified, as follows:

The culture of modern Philippines is derived from Spain and the Americas.

When referring to the citizens of the Philippines, use the terms Filipino and Filipina.

Filipino (a man or woman)
Filipinos (a group of men, or a group of men and women)
Filipina (a woman)
Filipinas (a group of women)

The language of the Philippines is Filipino.

Plural Forms of Some Words

This list represents the preferred forms that we use at the Bloomberg School.

Policymaker(s)

One word. See -maker.

Possessives

See Apostrophes.

Points of the compass

For proper usage of the words "north," "south," "east" and "west," see Regional Terms.

Post- (prefix)

As a general rule, we try to eliminate use of the hyphen after the prefix post-.

postabortion
postcoital
postdoctoral
postoperative
postpartum
posttraumatic

But sometimes there must be exceptions.

post-conception
post-contraception
post-Darwinian
post-Victorian

Use your best judgment, and, if you are uncertain, check an American language dictionary.

Posttraumatic stress disorder (PTSD)

Although we eschew the hyphen in posttraumatic, we currently continue to use the commonly recognized acronym PTSD.

Postal abbreviations of state names

When to use postal abbreviations
When publishing an entire address that includes a zip code for readers’ mailing purposes, use the two-letter postal abbreviation for states, which are in all-caps.

In running text
In running text, use the following abbreviations (not the U.S. Postal Service's two-letter abbreviations) for state names that follow names of cities or towns:

Ala., Ariz., Ark., Calif., Colo., Conn., D.C., Del., Fla., Ga., Ill., Ind., Kan., Ky., La., Md., Mass., Mich., Minn., Miss., Mo., Mont., Neb., Nev., N.C., N.D., N.H., N.J., N.M., N.Y., Okla., Ore., Pa., R.I., S.C., S.D., Tenn., Vt., Va., Wash., W.Va., Wis., Wyo.

Never abbreviate the names of these states:

Alaska, Hawaii, Idaho, Iowa, Maine, Ohio, Texas, and Utah.

Pre- (prefix)

As a general rule, we try to eliminate use of the hyphen after the prefix pre-.

predoctoral
preeminent
prefascist
prefeminist
preschool
pretax

But sometimes there must be exceptions.

pre-Christian
pre-Raphaelite
pre-K
pre-Socratic

If you are uncertain, check an American language dictionary.

Prefixes

When to close up compounds
Compounds formed with the prefixes listed below are usually closed up (no hyphen).

ante, anti, bi, bio, co, counter, extra, infra, inter, intra, life, macro, meta, micro, mid, mini, multi, neo, non, over, post, pre, pro, proto, pseudo, re, semi, socio, sub, super, supra, trans, ultra, un, under

When to hyphenate
Use a hyphen if the prefix is attached to a proper noun or to more than one word, or if closing up the word would make it confusing or ambiguous.

anti-Semitic oratory
pre-20th-century poet
co-op (versus coop)
anti-intellectual
A small-business manager operates a business that is small; a small business manager is diminutive in stature.

Prepositions

It is OK to end a sentence with a preposition. (Remember Churchill’s response when someone corrected him for doing s “This is something up with which I will not put.”)

Principal investigator

Principal, not principle. Also abbreviated as PI or P.I.

Professor in, professor of

When referring to a department within the Bloomberg School, we use professor in.

George Comstock, professor in Epidemiology ...
Michael Scott, associate professor in the W. Harry Feinstone Department of Molecular Microbiology and Immunology ...

When referring to someone elsewhere, we use professor of.

George Costanza, assistant professor of biostatistics ...
Elizabeth Lemon, professor of biochemistry ...

Protozoan, protozoa

Singular = protozoan
Plural = protozoa
Adjective = protozoan

The protozoan Plasmodium falciparum, which causes malaria ... .

Protozoa are unicellular, hermaphroditic organisms.

Protozoan sex spans the gamut, from asexual to sexual to a combination.

When referring to a particular protozoan, the genus name is italicized and initial-capped, and the species name is italicized (but not capitalized), as follows:

Cryptosporidium parvum 
Giardia lamblia 
Leishmania spp.
Plasmodium spp.

When abridging the name of a protozoan, we do so as follows:

C. parvum
G. lamblia

The name of the disease caused by the protozoan is neither italicized nor capped (unless it contains a proper name).

cryptosporidiosis
giardiasis
leishmaniasis
Baghdad boil